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Exhibit 13.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the annual report of Hellenic Telecommunications S.A. (the "Company") on Form 20-F for the fiscal year ended December 31, 2003, as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Panagis Vourloumis, Chairman & Managing Director of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

1.

The report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2.

The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: July 15, 2004

/s/  PANAGIS VOURLOUMIS Panagis Vourloumis
Chairman & Managing Director

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Exhibit 13.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002