Exhibit 99(a)


                               TXU US HOLDINGS COMPANY
                         Certificate Pursuant to Section 906
                           of Sarbanes - Oxley Act of 2002
                                 CERTIFICATION OF CEO


        The undersigned, Erle Nye, Chairman of the Board and Chief Executive
of TXU US Holdings Company (the "Company"), DOES HEREBY CERTIFY that:

     1. The Company's Current Report on Form 8-K related to TXU Energy Company
        LLC filed on or about May 20, 2003 ("the Report") fully complies with
        the requirements of section 13(a) or 15(d) of the Securities Exchange
        Act of 1934, as amended; and

     2. Information contained in the Report fairly presents, in all material
        respects, the financial condition and results of operations of TXU
        Energy Company LLC.

        IN WITNESS WHEREOF, the undersigned has caused this instrument to be
executed this 20th day of May, 2003.




                                           /s/ Erle Nye
                                        --------------------------------
                                        Name:  Erle Nye
                                        Title: Chairman of the Board
                                               and Chief Executive















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