SC TO-T/A

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE TO
(Rule 14d-100)

TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR 13(e)(1)
OF THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 13)

Alcan Inc.
(Name of Subject Company (Issuer))

Rio Tinto Canada Holding Inc.
an indirect wholly-owned subsidiary of Rio Tinto plc
and
Rio Tinto plc
(Names of Filing Persons (Offeror))

Common Shares
(Title of Class of Securities)

(013716105)
(CUSIP Number of Class of Securities)

Ben Mathews
Rio Tinto plc
6 St James's Square
London SW1Y 4LD
United Kingdom
Tel: 011 44 20 7930 2399
with a copy to
Thomas B. Shropshire, Jr.
Linklaters LLP
One Silk Street
London EC2Y 8HQ
United Kingdom
Tel: 011 44 20 7456 2000

(Name, Address and Telephone Number of Person Authorized
to Receive Notices and Communications on Behalf of Bidders)

CALCULATION OF FILING FEE:

Transaction Valuation(1)	Amount of Filing Fee(1)(2)
$19,065,207,127	$585,302

(1)

For purposes of calculating the filing fee pursuant to Rule 0-11(d) only, the transaction value of the Alcan Common Shares to be received by Rio Tinto, assuming acceptance of the Offer by holders in the United States, is calculated as follows: 188,764,427 Alcan Common Shares in the United States, representing 50% of the entire issued share capital, multiplied by $101, the cash consideration being offered per Alcan Common Share, which yields $19,065,207,127, multiplied by 0.0000307, which yields $585,302. Each of the capitalized terms used is defined below.

(2)

Sent via wire transfer to the SEC on July 24, 2007.

o

Check box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

Amount Previously Paid	Filing Party:
Form or Registration No.:	Date Field:

o

Check the box if the filing relates solely to preliminary communications made before commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the statement relates:

ý

third-party tender offer subject to Rule 14d-1.

o

issue tender offer subject to Rule 13e-4.

o

going-private transaction subject to Rule 13e-3.

o

amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer: o

        This Amendment No. 13 further amends and supplements the Tender Offer Statement on Schedule TO originally filed with the Securities and Exchange Commission on July 24, 2007 (as amended, the "Schedule TO"), by Rio Tinto plc and by Rio Tinto Canada Holding Inc., an indirect wholly-owned subsidiary of Rio Tinto. Unless otherwise defined herein, all capitalized terms shall have the meaning given to them in the Circular filed as Exhibit (a)(1)(A) to the Schedule TO.

        On September 17, 2007, Rio Tinto released a notice of extension of the Offer. This notice of extension of the Offer has been filed as Exhibit (a)(5)(T) hereto and is incorporated herein by this reference.

        Rio Tinto also issued a letter to shareholders of Alcan announcing the extension of the Offer, dated September 17, 2007. This letter has been filed as Exhibit (a)(5)(U) hereto and is incorporated herein by this reference.

        In addition, Rio Tinto issued a press release announcing the extension of the Offer, dated September 17, 2007. This press release has been filed as Exhibit (a)(5)(V) hereto and is incorporated herein by this reference.

ITEM 12. EXHIBITS

(a)(1)(A)°	Circular, dated July 24, 2007.
(a)(1)(B)°	Form of Letter of Transmittal.
(a)(1)(C)°	Form of Notice of Guaranteed Delivery.
(a)(1)(D)°	Form of Letter to Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees.
(a)(1)(E)°	Form of Letter to Clients for use by Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees.
(a)(5)(A)°	Summary Advertisement in The Wall Street Journal, dated July 24, 2007.
(a)(5)(B)°	Press release announcing commencement of the Offer, dated July 24, 2007.
(a)(5)(C)°	Transcript of interview with Bloomberg UK, dated July 12, 2007.
(a)(5)(D)°	Transcript of interview with CNBC Europe, dated July 12, 2007.
(a)(5)(E)°	Transcript of interview with CNN International, dated July 12, 2007.
(a)(5)(F)°	Transcript of interview with CNBC US, dated July 19, 2007.
(a)(5)(G)°	Management slide presentation by Rio Tinto plc, dated August 2, 2007.
(a)(5)(H)°	Script of management slide presentation by Rio Tinto plc, dated August 2, 2007.
(a)(5)(I)°	News release announcing half-year results, dated August 2, 2007.
(a)(5)(J)°	Transcript of interview with BNN, dated July 18, 2007.
(a)(5)(K)°	Transcript of interview with the Australian Broadcasting Corporation, dated July 23, 2007.
(a)(5)(L)°	Memorandum to managers of Rio Tinto and Alcan, dated August 2, 2007.
(a)(5)(M)°	Press release relating to the Offer, dated August 7, 2007.
(a)(5)(N)°	Frequently Asked Questions about the Rio Tinto Offer for Alcan Inc., dated August 20, 2007.
(a)(5)(O)°	Press release announcing extraordinary general meetings, dated August 24, 2007.
(a)(5)(P)°	Press release announcing US antitrust approval, dated August 27, 2007.
(a)(5)(Q)°	Press release announcing completion of loan syndication for financing of Alcan acquisition, dated August 30, 2007.
(a)(5)(R)°	Press release announcing Canadian Competition Act clearance, dated August 30, 2007.
(a)(5)(S)°	Press release announcing Rio Tinto plc Extraordinary General Meeting, dated September 14, 2007.
(a)(5)(T)	Notice of extension of the Offer, dated September 17, 2007.
(a)(5)(U)	Letter to shareholders of Alcan announcing the extension of the Offer, dated September 17, 2007.
(a)(5)(V)	Press release announcing the extension of the Offer, dated September 17, 2007.
(b)(1)°	Facility Agreement, dated July 12, 2007, among Rio Tinto, Credit Suisse, Deutsche Bank AG, London Branch, The Royal Bank of Scotland plc, and Societe Generale.
(d)(1)°	Support Agreement, dated July 12, 2007, among Alcan, the Offeror and Rio Tinto.
(d)(2)°	English language translation of undertakings and confirmations made by Rio Tinto and Offeror to the Government of Quebec and Alcan, dated July 11, 2007.
(d)(3)°	Confidentiality Agreement, dated April 11, 2007 between Alcan and Rio Tinto.
(d)(4)°	Amendment to Confidentiality Agreement, dated June 25, 2007.
(d)(5)°	Standstill Agreement, dated June 13, 2007, between Alcan and Rio Tinto.
(d)(6)°	Amendment to Support Agreement, dated July 20, 2007, among Alcan, the Offeror and Rio Tinto.
(g)°	None.
(h)°	None.

°

Previously filed with the SEC.

SIGNATURE

        After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date:  September 17, 2007	RIO TINTO PLC
	By:	/s/  GUY ELLIOTT
	Name: Title:	Guy Elliott Finance Director
	RIO TINTO CANADA HOLDING INC.
	By:	/s/  IAN RATNAGE
	Name: Title:	Ian Ratnage Director

EXHIBIT INDEX

(a)(1)(A)°	Circular, dated July 24, 2007.
(a)(1)(B)°	Form of Letter of Transmittal.
(a)(1)(C)°	Form of Notice of Guaranteed Delivery.
(a)(1)(D)°	Form of Letter to Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees.
(a)(1)(E)°	Form of Letter to Clients for use by Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees.
(a)(5)(A)°	Summary Advertisement in The Wall Street Journal, dated July 24, 2007.
(a)(5)(B)°	Press release announcing commencement of the Offer, dated July 24, 2007.
(a)(5)(C)°	Transcript of interview with Bloomberg UK, dated July 12, 2007.
(a)(5)(D)°	Transcript of interview with CNBC Europe, dated July 12, 2007.
(a)(5)(E)°	Transcript of interview with CNN International, dated July 12, 2007.
(a)(5)(F)°	Transcript of interview with CNBC US, dated July 19, 2007.
(a)(5)(G)°	Management slide presentation by Rio Tinto plc, dated August 2, 2007.
(a)(5)(H)°	Script of management slide presentation by Rio Tinto plc, dated August 2, 2007.
(a)(5)(I)°	News release announcing half-year results, dated August 2, 2007.
(a)(5)(J)°	Transcript of interview with BNN, dated July 18, 2007.
(a)(5)(K)°	Transcript of interview with the Australian Broadcasting Corporation, dated July 23, 2007.
(a)(5)(L)°	Memorandum to managers of Rio Tinto and Alcan, dated August 2, 2007.
(a)(5)(M)°	Press release relating to the Offer, dated August 7, 2007.
(a)(5)(N)°	Frequently Asked Questions about the Rio Tinto Offer for Alcan Inc., dated August 20, 2007.
(a)(5)(O)°	Press release announcing extraordinary general meetings, dated August 24, 2007.
(a)(5)(P)°	Press release announcing US antitrust approval, dated August 27, 2007.
(a)(5)(Q)°	Press release announcing completion of loan syndication for financing of Alcan acquisition, dated August 30, 2007.
(a)(5)(R)°	Press release announcing Canadian Competition Act clearance, dated August 30, 2007.
(a)(5)(S)°	Press release announcing Rio Tinto plc Extraordinary General Meeting, dated September 14, 2007.
(a)(5)(T)	Notice of extension of the Offer, dated September 17, 2007.
(a)(5)(U)	Letter to shareholders of Alcan announcing the extension of the Offer, dated September 17, 2007.
(a)(5)(V)	Press release announcing the extension of the Offer, dated September 17, 2007.
(b)(1)°	Facility Agreement, dated July 12, 2007, among Rio Tinto, Credit Suisse, Deutsche Bank AG, London Branch, The Royal Bank of Scotland plc, and Societe Generale.
(d)(1)°	Support Agreement, dated July 12, 2007, among Alcan, the Offeror and Rio Tinto.
(d)(2)°	English language translation of undertakings and confirmations made by Rio Tinto and Offeror to the Government of Quebec and Alcan, dated July 11, 2007.
(d)(3)°	Confidentiality Agreement, dated April 11, 2007 between Alcan and Rio Tinto.
(d)(4)°	Amendment to Confidentiality Agreement, dated June 25, 2007.
(d)(5)°	Standstill Agreement, dated June 13, 2007, between Alcan and Rio Tinto.
(d)(6)°	Amendment to Support Agreement, dated July 20, 2007, among Alcan, the Offeror and Rio Tinto.
(g)°	None.
(h)°	None.

°

Previously filed with the SEC.

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ITEM 12. EXHIBITS
SIGNATURE
EXHIBIT INDEX

EX-99.(A)(5)(T)

Exhibit (a)(5)(T)

This document is important and requires your immediate attention. If you have any questions as to how to deal with it, you are encouraged to consult your investment dealer, stockbroker, bank manager, accountant, lawyer or other professional advisor. It should be read in conjunction with the take-over bid circular of Rio Tinto Canada Holding Inc. dated July 24, 2007.

The Offer has not been approved or disapproved by the SEC or any securities regulatory authority in Canada or the United States or any other jurisdiction nor has any securities regulatory authority expressed an opinion about, or passed upon the fairness or merits of, the Offer contained in this document or the adequacy of the information contained in this document. Any representation to the contrary is unlawful.

NOTICE OF EXTENSION

by

RIO TINTO CANADA HOLDING INC.,

an indirect wholly-owned subsidiary of Rio Tinto plc,

of its

OFFER TO PURCHASE FOR CASH

all of the outstanding Common Shares of

ALCAN INC.

at a price of U.S.$101 Per Common Share

Rio Tinto Canada Holding Inc. (referred to herein as the ‘‘Offeror’’) hereby gives notice that it is extending the offer dated July 24, 2007 (the ‘‘Offer’’) to purchase each issued and outstanding common share of Alcan Inc. (‘‘Alcan’’), together with the associated rights (the ‘‘Alcan Rights’’) (and, together with the common shares of Alcan, the ‘‘Alcan Common Shares’’) issued and outstanding under Alcan’s Shareholder Rights Plan which is described under ‘‘Shareholder Rights Plan’’ in the take-over bid circular of the Offeror dated July 24, 2007 (the ‘‘Circular’’), for U.S.$101 (equivalent to Cdn$103.96 based on the September 14, 2007 Bank of Canada Noon Rate) per Alcan Common Share in cash (less any applicable withholding taxes and without interest) (the ‘‘Offer Consideration’’) upon the terms and subject to the conditions set forth in the Offer, as extended or supplemented by this Notice of Extension, and in the letter of transmittal (the ‘‘Letter of Transmittal’’) that accompanied the Circular (printed on blue paper). The Offer will be open for acceptance until 6:00 p.m., Eastern Time (Canada), on October 23, 2007, unless extended or withdrawn by the Offeror (the ‘‘Expiry Time’’).

THE OFFER HAS BEEN EXTENDED AND IS NOW OPEN FOR ACCEPTANCE UNTIL

6:00 P.M. (EASTERN TIME) ON OCTOBER 23, 2007.

Shareholders who have validly deposited and not withdrawn their Alcan Common Shares need take no further action to accept the Offer.

If you wish to accept the Offer, you should either (i) complete and sign the Letter of Transmittal (or a manually signed facsimile copy thereof) that accompanied the Circular in accordance with the instructions in the Letter of Transmittal and mail or deliver it together with the certificate(s) evidencing deposited Alcan Common Shares, and any other required documents, to Computershare Investor Services Inc., as depositary (the ‘‘Depositary’’), at any of its offices specified in the Letter of Transmittal, (ii) deposit your Alcan Common Shares under the Offer pursuant to the procedures for book-entry transfer set forth in the section entitled ‘‘Offer — Manner of Acceptance’’ of the Circular, or (iii) request your broker, dealer, commercial bank, trust company or other nominee to effect the transaction for you.

If your Alcan Common Shares are registered in the name of a broker, dealer, commercial bank, trust company or other nominee you must contact such broker, dealer, commercial bank, trust company or other nominee if you wish to deposit your Alcan Common Shares under the Offer.

The Dealer Managers for the Offer are:

In the United States:	In Canada:
Deutsche Bank Securities Inc.	CIBC World Markets Inc.
Toll Free: 1 (877) 221-7676	Toll Free: 1 (866) 744-2030 (English)
	Telephone: 1 (514) 847-6638 (French)
September 17, 2007	(continued on next page)

(continued from cover)

This notice of extension (the ‘‘Notice of Extension’’) should be read in conjunction with the Circular, the notice of guaranteed delivery (the ‘‘Notice of Guaranteed Delivery’’) and Letter of Transmittal that accompanied the Circular and the Tender Offer Statement on Schedule TO, as amended, as filed with the U.S. Securities and Exchange Commission (the ‘‘SEC’’). Unless the context requires otherwise or unless otherwise defined herein or amended hereby, defined terms used in this Notice of Extension have the same meaning as in the Circular.

If you wish to deposit your Alcan Common Shares under the Offer and (i) the certificates representing your Alcan Common Shares are not immediately available, (ii) you cannot deliver the certificates representing Alcan Common Shares and/or Alcan Rights, if applicable, and all other required documents to the Depositary before the Expiry Time, (iii) you cannot comply with the procedures for book-entry transfer on a timely basis, or (iv) the Separation Time (as defined under the section entitled ‘‘Offer — Shareholder Rights Plan’’ of the Circular) has occurred before the Expiry Time but Rights Certificates have not been distributed to Alcan shareholders before the Expiry Time, your Alcan Common Shares may nevertheless be validly deposited under the Offer in compliance with the procedures for guaranteed delivery using the Notice of Guaranteed Delivery. See the section entitled ‘‘Offer — Manner of Acceptance’’ of the Circular.

Questions or requests for assistance may be directed to the Information Agent at its address and telephone numbers, or either of the Dealer Managers at their telephone numbers, in each case, as set forth on the back cover of this document. Requests for additional copies of this document, the Letter of Transmittal and the Notice of Guaranteed Delivery may be directed to the Information Agent, and copies will be furnished promptly at the Offeror’s expense. You may also contact your broker, dealer, commercial bank, trust company or other nominee for assistance concerning the Offer.

The Offeror has not authorized anyone to provide any information or make any representation about the Offeror or its affiliates that is different from, or in addition to, the information and representations contained in the Circular as amended or supplemented by this Notice of Extension or in any materials regarding the Offeror or its affiliates accompanying this document or incorporated by reference herein or therein.

You should not rely on any information or any representation regarding the Offeror or its affiliates not contained in this document or not contained in any material accompanying this document or incorporated by reference in it. While the Offer is being made to all holders of Alcan Common Shares, this document does not constitute an offer or a solicitation in any jurisdiction in which such offer or solicitation is unlawful. The Offer is not being made in, nor will deposits be accepted in, any jurisdiction in which the making or acceptance thereof would not be in compliance with the laws of such jurisdiction.

THIS NOTICE OF EXTENSION, THE CIRCULAR AND RELATED LETTER OF TRANSMITTAL AND, IF APPLICABLE, NOTICE OF GUARANTEED DELIVERY CONTAIN IMPORTANT INFORMATION AND YOU SHOULD CAREFULLY READ THEM IN THEIR ENTIRETY BEFORE MAKING A DECISION WITH RESPECT TO THE OFFER. ADDITIONAL INFORMATION ABOUT THE RIO TINTO GROUP AND ALCAN IS AVAILABLE AT THE INTERNET WEBSITES MAINTAINED BY THE SEC AND CANADIAN SECURITIES REGULATORY AUTHORITIES AT WWW.SEC.GOV AND WWW.SEDAR.COM, RESPECTIVELY.

THIS NOTICE OF EXTENSION, THE CIRCULAR, THE TENDER OFFER STATEMENT ON SCHEDULE TO PREPARED BY THE OFFEROR AND THE SOLICITATION/RECOMMENDATION STATEMENT ON SCHEDULE 14D-9 PREPARED BY ALCAN CAN BE OBTAINED FROM THE SEC’S WEBSITE FREE OF CHARGE. THE INFORMATION CONTAINED ON THE WEBSITES IS NOT INCORPORATED BY REFERENCE INTO THE OFFER AND YOU SHOULD NOT CONSIDER INFORMATION CONTAINED ON THE WEBSITES AS PART OF THE OFFER. PLEASE SEE THE SECTION ENTITLED ‘‘WHERE YOU CAN FIND ADDITIONAL INFORMATION’’ IN THE CIRCULAR.

ii

NOTICE TO SHAREHOLDERS IN FRANCE

The Offer is made to holders in France of Alcan Common Shares admitted to trading on Euronext-Paris (the ‘‘French Shares’’). An announcement including the main information relating to the Offer documents has been prepared and released pursuant to article 231-24 of the Autorité des marchés financiers (‘‘AMF’’) General Regulation (Communiqué établi conformément à l’article 231-24 du Règlement général) and contains information relating to how and in which time limit Alcan Shareholders residing in France can accept the Offer. The offer document and the announcement prepared pursuant to article 231-24 of the AMF General Regulation are available free of charge to the holders of French Shares registered with Euroclear France who request it from Citi France, Global Transaction Services, Operations department, 19 le Parvis la Défense 7, 92073 Paris la Défense. They are also available on the internet at the following address: www.computershare.com/Rio-AlcanFrenchofferdocument.

HOLDERS IN BELGIUM OF SHARES AND IDRs

The Offer is made to holders in Belgium of shares and/or certificates admitted to trading on Euronext Brussels (the ‘‘IDRs’’). A Belgian supplement, addressing issues specific to holders of shares and/or IDRs in Belgium (the ‘‘Belgian Supplement’’) was approved by the Belgian Banking, Finance and Insurance Commission on August 2, 2007. The offer document and the Belgian Supplement are available free of charge to the investors in Belgium who request it from the Belgian branch of Citibank International plc, Department GTS Operations, 4th floor, boulevard Général Jacques 263G, 1050 Brussels. They are also available on the internet at the following address: www.computershare.com/Rio-AlcanBelgianofferdocument. Further details of how the extension of the Offer impacts Belgian shareholders are contained in the press release released today.

NOTICE TO HOLDERS OF OPTIONS

The Offer is made only for Alcan Common Shares. The Offer is not made for any options or any other rights (other than Alcan Rights) to acquire Alcan Common Shares (including options to purchase shares of Pechiney).

EXCHANGE RATE INFORMATION

In this document, ‘‘$’’ and ‘‘U.S.$’’ refer to U.S. dollars, and ‘‘Cdn$’’ refers to Canadian dollars. On September 14, 2007, the exchange rate for one U.S. dollar expressed in Canadian dollars based upon the Bank of Canada Noon Rate was Cdn$1.0293.

FORWARD-LOOKING STATEMENTS

Certain statements and assumptions in this Notice of Extension and in the Circular about the Offeror, Rio Tinto and Alcan contain or are based on ‘‘forward-looking’’ information and involve risks and uncertainties. Such statements include, but are not limited to, statements with regard to the outcome of the Offer, and may be (but are not necessarily) identified by the use of phrases such as ‘‘will’’, ‘‘expect’’, ‘‘intends’’ ‘‘anticipate’’, and ‘‘believe’’. By their nature, forward-looking statements involve risk and uncertainty because they relate to events and depend on circumstances that will occur in the future and may be outside the control of the Offeror, Rio Tinto or Alcan. Actual results and developments may differ materially from those expressed or implied in such statements because of a number of factors, including the outcome of the Offer and such other factors identified in Rio Tinto’s most recent Annual Report on Form 20-F filed with the SEC or Form 6-Ks furnished to the SEC or Alcan’s most recent periodic and current reports on Form 10-K, 10-Q or 8-K filed with the SEC (as the case may be).

iii

NOTICE OF EXTENSION

TO: THE HOLDERS OF ALCAN COMMON SHARES

This Notice of Extension amends and supplements the Offer, the Circular, and the Letter of Transmittal and the Notice of Guaranteed Delivery which accompanied the Circular, and should be read in conjunction therewith.

Except as otherwise set forth in this Notice of Extension, the terms and conditions previously set forth in the Circular, as varied, amended and supplemented by the Letter of Transmittal and the Notice of Guaranteed Delivery continue to be applicable in all respects.

Unless the context requires otherwise or unless otherwise defined herein or amended hereby, defined terms used in this Notice of Extension have the same meaning as in the Circular.

1.      Extension of the Offer

The Offeror hereby gives notice that it has extended the expiry time of the Offer from 6:00 p.m., Eastern Time (Canada), on September 24, 2007 to 6:00 p.m., Eastern Time (Canada), on October 23, 2007. Accordingly, all references to September 24, 2007 in the Offer and Circular, the Letter of Transmittal and the Notice of Guaranteed Delivery (to the extent they refer to the expiry time of the Offer) are amended to refer to October 23, 2007, and all references to ‘‘Expiry Time’’ shall mean 6:00 p.m., Eastern Time (Canada), on October 23, 2007.

2.      Time for Acceptance

The Offer is now open for acceptance until 6:00 P.M. (Eastern Time, Canada) on October 23, 2007, unless it is further extended or withdrawn.

3.      Manner of Acceptance

The procedure for accepting the Offer is described on page 12 of the Circular under the heading ‘‘Manner of Acceptance’’.

4.      Supplemental Information

Manner of Acceptance

The deadline for delivering certificates with respect to shares deposited under the bid using the guaranteed delivery procedures is 5:00 p.m. (local time at the place of deposit) on the second TSX trading day following the date of the Expiry Time. If Rights separate from the Alcan Common Shares but Rights Certificate(s) are not available at the time a shareholder deposits its Alcan Common Shares pursuant to the Offer, the Rights Certificate(s) must be delivered to the Depositary, before 5:00 p.m. (local time at the place of deposit) on the second TSX trading day following the date that Rights Certificate(s) are distributed. References to ‘‘third trading day on the TSX’’ in the Circular under the headings ‘‘Manner of Acceptance — Letter of Transmittal’’ and ‘‘Manner of Acceptance — Procedures for Guaranteed Delivery’’, on pages 13 and 15 of the Circular, should be read as ‘‘second trading day on the TSX’’ so as to agree with what is stated in the Letter of Transmittal and the Notice of Guaranteed Delivery, which were delivered with the Circular.

Support Agreement — Expense Reimbursement

In the first paragraph under the heading ‘‘Expense Reimbursement’’ on page 44 of the Circular, the expression ‘‘Alcan Termination Payment’’ is deleted and replaced with ‘‘Rio Tinto Termination Payment’’.

In the second paragraph under the heading ‘‘Expense Reimbursement’’ on page 45 of the Circular, the expression ‘‘Rio Tinto Termination Payment’’ is deleted and replaced with ‘‘Alcan Termination Payment’’.

1

Source and Amount of Funds

The Facility Agreement is described in the Circular as comprising three term facilities and one revolving facility for a total amount of up to U.S.$40 billion. It should have been described as comprising two term facilities and two revolving facilities for a total amount of up to U.S.$40 billion. Accordingly, the second sentence of the second paragraph under the heading ‘‘Source and Amount of Funds’’ on page 8 of the Circular is deleted and replaced with ‘‘The Facility Agreement comprises two term facilities and two revolving facilities (including a swingline facility) up to a total amount of U.S.$40 billion.’’

Similarly, the second sentence of the second paragraph under the heading ‘‘Source and Amount of Funds’’ on page 49 of the Circular is deleted and replaced with ‘‘The Facility Agreement comprises two term facilities and two revolving facilities (including a swingline facility) up to a total amount of U.S.$40 billion’’.

The fourth and fifth paragraphs in that section on page 49 are deleted in their entirety and replaced with the following:

‘‘The Facility Agreement contains covenants to be made by and restrictions on Rio Tinto and the Offeror, including that they be required to observe certain customary covenants including but not limited to (i) maintenance of authorisations; (ii) compliance with laws; (iii) change of business; (iv) negative pledge (subject to certain carve outs); (v) environmental laws and licences; and (vi) subsidiaries incurring financial indebtedness.

The term facilities are to be repaid on the termination of their respective 364-day (subject to exercise of the extension option), and 5-year and 1-Business Day terms. No amounts repaid by the borrowers under the term facilities may be re-borrowed. Facilities B and C will cease to be available one month prior to their respective 3-year and 5-year termination dates. All loans made under Facilities B and C are to be repaid on their respective termination dates.’’

5.      Take up of and Payment for Deposited Common Shares

Provided all of the conditions to the Offer shall have been waived by the Offeror or satisfied, the Offeror will take up and pay for all of the Alcan Common Shares tendered under the Offer promptly and, in any event, not later than two Business Days following the time at which the Offeror becomes entitled to take up such Alcan Common Shares under the Offer pursuant to applicable securities laws. Any Alcan Common Shares validly deposited during the Subsequent Offering Period will be taken up immediately and paid for promptly. The irrevocable undertaking set out in the Offer not to take up any Alcan Common Shares prior to the Expiry Time is required under Alcan’s Shareholder Rights Plan and was intended to operate only with respect to the initial 60-day deposit period, and will not apply with respect to this or any subsequent extension of the deposit period.

Shareholders are referred to page 24 of the Circular under the section entitled ‘‘Take Up of, and Payment for, Deposited Alcan Common Shares’’ for details as to the take up of and payment for Alcan Common Shares under the Offer.

6.      Variations to the Offer

The Circular, the Letter of Transmittal and the Notice of Guaranteed Delivery shall be read together with this Notice of Extension in order to give effect to the variations in the terms and conditions of the Offer and the changes to the information provided in the Circular, as varied, amended and supplemented by this Notice of Extension.

7.      Right to Withdraw

Alcan Common Shares deposited under the Offer may be withdrawn by or on behalf of the depositing Alcan shareholder (unless otherwise required or permitted by applicable law):

•at any time before Alcan Common Shares deposited under the Offer are taken up and paid for by the Offeror under the Offer;

2

•during the Subsequent Offering Period; provided, however, that this right of withdrawal will not apply in respect of Alcan Common Shares taken up and paid for by the Offeror prior to the Subsequent Offering Period; or

•at any time before the expiration of the tenth day after the date upon which either: (a) a notice of change is first mailed, delivered or otherwise properly communicated, relating to a change that has occurred in the information contained in the Offer or the Circular, as amended from time to time, and such change is one that would reasonably be expected to affect the decision of an Alcan shareholder to accept or reject the Offer (other than a change that is not within the control of the Offeror or its affiliates); provided that such change occurs before the Expiry Time or after the Expiry Time but before the expiration of all rights of withdrawal in respect of the Offer; or (b) a notice of variation concerning a variation of the terms of the Offer (other than a variation consisting solely of an increase in the Offer Consideration where the time for deposit is not extended for a period greater than 10 days) is first mailed, delivered or otherwise properly communicated.

Shareholders are referred to page 25 of the Circular under the section entitled ‘‘Right to Withdraw’’ for a description of the procedures for exercising the right to withdraw Common Alcan Shares deposited under the Offer.

8.      Statutory Rights

Securities legislation in the provinces and territories of Canada provides you with, in addition to any other rights you may have at law, one or more rights of rescission or price revision or to damages, if there is a misrepresentation in a circular or notice that is required to be delivered to you. However, such rights must be exercised within prescribed time limits. You should refer to the applicable provisions of the securities legislation of your province or territory for particulars of those rights or consult with a lawyer.

9.      Directors’ Approval

The contents of this Notice of Extension have been approved and the sending thereof to the Alcan shareholders has been authorized by the board of directors of the Offeror.

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APPROVAL AND CERTIFICATE OF RIO TINTO CANADA HOLDING INC.

The contents of this Notice of Extension have been approved by, and the sending thereof to the Alcan shareholders has been authorized by, the board of directors of Rio Tinto Canada Holding Inc. The foregoing contains no untrue statement of a material fact and does not omit to state a material fact that is required to be stated or that is necessary to make a statement not misleading in the light of the circumstances in which it was made.

IAN C. RATNAGE		MICHEL JUTRAS
President		Secretary
	On behalf of the board of directors
MICHEL JUTRAS	IAN C. RATNAGE		JOCELIN PARADIS
Director	Director		Director

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The Depositary for the Offer is:

COMPUTERSHARE INVESTOR SERVICES INC.

In Canada

By Mail:	By Registered Mail, Hand or by Courier:
Computershare Investor Services Inc. P.O. Box 702531 Adelaide Street East Toronto, Ontario M5C 2T1 Attention: Corporate Actions	Computershare Investor Services Inc. 100 University Avenue 9th Floor Toronto, Ontario M5J 2Y1 Attention: Corporate Actions

Toll Free (North America): 1-866-624-1341
Overseas: +1 (514) 982-7555
Email: corporateactions@computershare.com

Montréal		Vancouver	Calgary
By Hand:	Registered Mail or	By Registered Mail,	By Registered Mail,
	by Courier:	Hand or by Courier:	Hand or by Courier:
650 de Maisonneuve	1500 University Street	510 Burrard Street	Western Gas Tower
Blvd West	Suite 700	2nd Floor	Suite 600
Suite 700	Montréal, Quebec	Vancouver,	530 8th Avenue S.W.
Montréal, Quebec	H3A 3S8	British Columbia	Calgary, Alberta
H3A 3S8		V6C 3B9	T2P 3S8

In the U.S.:

By Mail:	By Hand or by Courier:
c/o Computershare Trust Company, N.A.	c/o Computershare Trust Company, N.A.
Attention: Corporate Actions	Attention: Corporate Actions
P.O. Box 4301	4250 Royall Street
Providence, Rhode Island 02940-3014	Canton, Massachusetts 02021

The Dealer Managers for the Offer are:

In the United States:	In Canada:
Deutsche Bank Securities Inc.	CIBC World Markets Inc.
60 Wall Street	161 Bay Street, 6th Floor
New York, New York 10005	Toronto, Ontario
Toll Free: 1 (877) 221-7676	M5J 2S8
	Toll Free: 1 (866) 744-2030 (English)
	Telephone: (514) 847-6638 (French)

The Information Agent for the Offer is:

100 University Avenue

11th Floor, South Tower

Toronto, Ontario

M5J 2Y1

North American Toll Free: 1 (888) 605-7629

European Union Free Call: 00 800 6540 6540

Australia Free Call: 1 (800) 216 071

EX-99.(A)(5)(U)

Exhibit (a)(5)(U)

September 17, 2007

Dear Shareholder of Alcan Inc.:

We are writing to inform you that Rio Tinto Canada Holding Inc. (the ‘‘Offeror’’) is extending the acceptance period of its offer to acquire all of the issued and outstanding shares of Alcan Inc. (‘‘Alcan’’) for US$101 per common share (the ‘‘Offer’’). Enclosed with this letter is a Notice of Extension which contains further information about the Offer. You should read the Notice of Extension in conjunction with this letter, which together update and modify the Circular dated July 24, 2007 which was previously mailed to you. The Offer will now be open for acceptance until 6:00 p.m. Eastern Time (Canada), on October 23, 2007, unless extended or withdrawn by the Offeror.

Recent Developments

On August 7, 2007, the Quebec Minister of Economic Development, Innovation and Export Trade announced that the Government of Quebec had accepted the conclusions of the Board of Directors of Alcan that the Offer respects the terms of the Continuity Agreement and that the Offeror and Rio Tinto plc have succeeded in demonstrating that the requirements of Section 3 of the Continuity Agreement have been met. No further approvals are required under the Continuity Agreement.

On August 26, 2007, Rio Tinto announced that it had received U.S. anti-trust clearance for the proposed acquisition of Alcan by the Offeror.

On August 30, 2007, Rio Tinto announced that Canadian Competition Act clearance for the proposed acquisition of Alcan by the Offeror had been obtained.

On September 4, 2007, Alcan completed the redemption of all of the Alcan Preferred Shares outstanding at a price of Cdn.$25.00 per share.

The acquisition of the shares of Alcan is subject to the approval of the shareholders of Rio Tinto plc and Rio Tinto Limited by ordinary resolution under a joint electorate procedure. The Extraordinary General Meeting of Rio Tinto plc was held on September 14, 2007 in London and the Extraordinary General Meeting of Rio Tinto Limited will be held on September 28, 2007, in Melbourne, Australia. The result of the voting on the Resolution will be announced after the meeting on September 28, 2007.

Yours faithfully,

Ian C. Ratnage
President

In connection with the Offer, an offer and takeover bid circular as well as ancillary documents such as a letter of transmittal and a notice of guaranteed delivery have been filed with the Canadian securities regulatory authorities and the SEC and an Alcan directors’ circular with respect to the Offer has also been filed. A Tender Offer Statement on Schedule TO and a Solicitation/Recommendation Statement on Schedule 14D-9 has also been filed with the SEC. The offer and takeover bid circular as well as other materials filed with the Canadian securities regulatory authorities are available electronically without charge at www.sedar.com. The Schedule TO and the Schedule 14D-9 are available electronically without charge at the SEC’s website, www.sec.gov. Materials filed with the SEC or the Canadian securities regulatory authorities may also be obtained without charge at Rio Tinto’s website, www.riotinto.com.

EX-99.(A)(5)(V)

Exhibit (a)(5)(V)

News release…

Date: 17 September 2007

Ref: PR550g

Offer for Alcan extended to October 23, 2007

Rio Tinto Canada Holding Inc. (“RTCH”) announces that the expiry date for the offer by RTCH to acquire all of the common shares of Alcan Inc. is being extended from September 24, 2007 to October 23, 2007.  The extension is necessary to permit conditions to the offer to be satisfied, including obtaining various regulatory approvals.  A formal notice of extension is being mailed today to all Alcan common shareholders.

As of the close of business on September 14, 2007, 495,139 shares had been deposited with the depositary under the offer and not withdrawn, representing less than 0.2 per cent of Alcan’s outstanding common shares on a fully-diluted basis. The offer is conditional on acceptances representing 66 2/3 per cent of Alcan shares.

About Rio Tinto

Rio Tinto is a leading international mining group headquartered in the UK, combining Rio Tinto plc, a London listed company, and Rio Tinto Limited, which is listed on the Australian Securities Exchange.

Rio Tinto’s business is finding, mining, and processing mineral resources. Major products are aluminium, copper, diamonds, energy (coal and uranium), gold, industrial minerals (borax, titanium dioxide, salt, talc) and iron ore. Activities span the world but are strongly represented in Australia and North America with significant businesses in South America, Asia, Europe and southern Africa.

Rio Tinto plc  6 St James’s Square  London SW1Y 4LD

Telephone 020 7930 2399  Fax 020 7930 3249

REGISTERED OFFICE:  6 St James’s Square  London SW1Y 4LD  Registered in England No. 719885

For further information, please contact:

Media Relations, London Christina Mills Office: +44 (0) 20 8080 1306 Mobile: +44 (0) 7825 275 605 Nick Cobban Office: +44 (0) 20 8080 1305 Mobile: +44 (0) 7920 041 003	Media Relations, Australia Ian Head Office: +61 (0) 3 9283 3620 Mobile: +61 (0) 408 360 101 Amanda Buckley Office: +61 (0) 3 9283 3627 Mobile: +61 (0) 419 801 349
Investor Relations, London Nigel Jones Office: +44 (0) 20 7753 2401 Mobile: +44 (0) 7917 227 365 David Ovington Office: +44 (0) 20 7753 2326 Mobile: +44 (0) 7920 010 978	Investor Relations, Australia Dave Skinner Office: +61 (0) 3 9283 3628 Mobile: +61 (0) 408 335 309 Investor Relations, North America Jason Combes Office: +1 (0) 801 685 4535 Mobile: +1 (0) 801 558 2645
Email: questions@riotinto.com
Website: www.riotinto.com
High resolution photographs available at: www.newscast.co.uk

Additional information

The offer to purchase all of the issued and outstanding common shares of Alcan for US$101 per common share in a recommended, all cash transaction (the “Offer”) is being made by Rio Tinto Canada Holding Inc. (the “Offeror”), an indirect wholly-owned subsidiary of Rio Tinto. The Offer represents a total consideration for Alcan common shares of approximately US$38.1 billion.

The Offer is open for acceptance until 6.00 p.m., Canadian Eastern Time, on October 23, 2007, unless extended. The Offer is subject to a number of conditions including valid acceptances by holders of not less than 66-2/3 per cent of Alcan shares on a fully diluted basis and the receipt of various governmental and regulatory approvals. The board of Rio Tinto has approved the transaction.  The Offer is expected to close in the fourth quarter of 2007.

This announcement is for information purposes only and does not constitute or form part of any offer or invitation to purchase, otherwise acquire, subscribe for, sell, otherwise dispose of or issue, or any solicitation of any offer to sell, otherwise dispose of, issue, purchase, otherwise acquire or subscribe for, any security. The Offer (as the same may be varied or extended in accordance with applicable law) is being made exclusively by means of, and subject to the terms and conditions set out in, the offer and takeover bid circular delivered to Alcan and filed with Canadian provincial securities regulators and the United States Securities and Exchange Commission (the “SEC”) and mailed to Alcan shareholders.

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The release, publication or distribution of this announcement in certain jurisdictions may be restricted by law and therefore persons in such jurisdictions into which this announcement is released, published or distributed should inform themselves about and observe such restrictions.

In connection with the Offer, an offer and takeover bid circular as well as ancillary documents such as a letter of transmittal and a notice of guaranteed delivery have been filed with the Canadian securities regulatory authorities and the SEC and an Alcan directors’ circular with respect to the Offer has also been filed. A Tender Offer statement on Schedule TO (the “Schedule TO”) and a Solicitation/Recommendation Statement on Schedule 14D-9 (the “Schedule 14D-9”) has also been filed with the SEC.

SHAREHOLDERS OF ALCAN ARE URGED TO READ THE OFFER AND TAKEOVER BID CIRCULAR (INCLUDING THE LETTER OF TRANSMITTAL AND NOTICE OF GUARANTEED DELIVERY), THE SCHEDULE TO (INCLUDING THE OFFER AND TAKEOVER BID CIRCULAR, LETTER OF TRANSMITTAL AND RELATED TENDER OFFER DOCUMENTS) AND THE SCHEDULE 14D-9 AS THEY CONTAIN IMPORTANT INFORMATION ABOUT THE OFFER.

The offer and takeover bid circular as well as other materials filed with the Canadian securities regulatory authorities are available electronically without charge at www.sedar.com. The Schedule TO and the Schedule 14D-9 are available electronically without charge at the SEC’s website, www.sec.gov. Materials filed with the SEC or the Canadian securities regulatory authorities may also be obtained without charge at Rio Tinto’s website, www.riotinto.com.

While the Offer is being made to all holders of Alcan common shares, this announcement does not constitute an offer or a solicitation in any jurisdiction in which such offer or solicitation is unlawful. The Offer is not being made in, nor will deposits be accepted in, any jurisdiction in which the making or acceptance thereof would not be in compliance with the laws of such jurisdiction. However, the Offeror may, in its sole discretion, take such action as it may deem necessary to extend the Offer in any such jurisdiction.

The Offer is made to holders in France of Alcan common shares admitted to trading on Euronext-Paris. An announcement including the main information relating to the Offer documents has been prepared and released pursuant to article 231-24 of the AMF General Regulation and contains information relating to how and in which time limit Alcan shareholders residing in France can accept this Offer. The offer document and the announcement prepared pursuant to article 231-24 of the AMF General Regulation are available free of charge to the holders of Alcan Shares registered with Euroclear France who request it from Citi France, Global Transaction Services, Operations department, 19 le Parvis la Défense 7, 92073 Paris la Défense. They are also available on the internet at the following address: www.computershare.com/Rio-AlcanFrenchofferdocument.

The Offer is made to holders in Belgium of Alcan common shares and/or certificates admitted to trading on Euronext Brussels (the “IDRs”). A Belgian supplement, addressing issues specific to holders of Alcan common shares and/or IDRs in Belgium (the “Belgian Supplement”) was approved by the Belgian Banking, Finance and Insurance Commission on 2 August 2007. The offer document and the Belgian Supplement are available free of charge to the investors in Belgium who request it from the Belgian branch of Citibank International plc, Department GTS Operations, 4th floor, boulevard Général Jacques 263G, 1050 Brussels. They are also available on the internet at the following address: www.computershare.com/Rio-AlcanBelgianofferdocument.

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