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                                                                   EXHIBIT 99.01

                            CERTIFICATION 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 Quarterly Report on Form 10-Q of Citigroup Inc. (the
"Company") for the quarterly period ended March 31, 2003, as filed with the
Securities and Exchange Commission on the date hereof (the "Report"), Sanford I.
Weill, as Chief Executive Officer of the Company, and Todd S. Thomson, as Chief
Financial Officer of the Company, each hereby certifies, 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.


/s/ Sanford I. Weill
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Sanford I. Weill
Chief Executive Officer
May 2, 2003


/s/ Todd S. Thomson
- --------------------------
Todd S. Thomson
Chief Financial Officer
May 2, 2003


This certification accompanies each Report pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002 and shall not, except to the extent required by the
Sarbanes-Oxley Act of 2002, be deemed filed by the Company for purposes of
Section 18 of the Securities Exchange Act of 1934, as amended.

A signed original of this written statement required by Section 906 has been
provided to the Company and will be retained by the Company and furnished to the
Securities and Exchange Commission or its staff upon request.