Inmarsat Investments 20-F 2004 FY Annual report (foreign)

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Exhibit 13.1

CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350

        In connection with the accompanying Annual Report on Form 20-F of Inmarsat Finance plc (the "Company") for the annual period ended December 31, 2004 (the "Periodic Report"), I, Andrew Sukawaty, Chief Executive Officer of the Company, hereby certify pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that, to the best of my knowledge the Periodic Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934 and the information contained in the Periodic Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/  ANDREW SUKAWATYAndrew Sukawaty
Chief Executive Officer

Date: April 29, 2005

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CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350