FFB:EMT

                                                                     May 9, 2007

Deutsche Bank Trust Company Americas,
  as Depositary under the Deposit Agreement
  referred to below
60 Wall Street
New York, NY 10005
United States

Ladies and Gentlemen:

    We refer to the Registration Statement on Form F-6 (the "Registration
Statement") relating to American Depositary Shares (as defined in the Deposit
Agreement) evidenced by American Depositary Receipts (as defined in the Deposit
Agreement), each American Depositary Receipt representing fifty shares of
Tongkah Harbour Public Company Limited (the "Company"). Terms used herein and
not defined herein shall have the meanings assigned to them in the Deposit
Agreement appearing as Exhibit (1) to the Registration Statement (the "Deposit
Agreement").

    In rendering the opinions set forth herein, we have assumed that (i) the
Deposit Agreement will have been duly authorized, executed and delivered by the
Company and will constitute a valid and legally binding obligation of the
Company enforceable against it in accordance with its terms, (ii) the relevant
Deposited Securities will have been duly deposited with a Custodian under and in
accordance with all applicable laws and regulations, (iii) that the choice of
New York law contained in the Deposit Agreement is legal and valid under the
laws of the Kingdom of Thailand and (iv) that insofar as any obligation under
the Deposit Agreement is to be performed in, or by a party organized under the
laws of, any jurisdiction outside of the United States of America, its
performance will not be illegal or ineffective in any jurisdiction by virtue of
the law of that jurisdiction.

    Based upon and subject to the foregoing, we are of the opinion that the
American Depositary Shares covered by the Registration Statement, when evidenced
by Receipts that are duly executed and delivered by the Depositary and issued in
accordance with the terms of


Deutsche Bank Trust Company Americas

May 9, 2007

the Deposit Agreement, will be validly issued and will entitle the registered
holders thereof to the rights specified in the Deposit Agreement and those
Receipts.

    The foregoing opinion is limited to the federal laws of the United States
and the laws of the State of New York and we express no opinion as to the laws
of any other jurisdiction.

    We hereby consent to the use of this opinion as Exhibit (4) to the
Registration Statement. In giving such consent, we do not admit hereby that we
are within the category of persons whose consent is required under Section 7 of
the Securities Act of 1933.

                                                    Very truly yours,


                                                    /s/ White & Case LLP


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