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                                                                  EXHIBIT 32.1

                                 CERTIFICATION

     I, Ronald J. Turner, President and Chief Executive Officer of TC
PipeLines GP, Inc., the general partner of TC PipeLines, LP (the
Partnership), in compliance with 18 U.S.C. Section 1350, as adopted pursuant
to Section 906 of the Sarbanes-Oxley Act of 2002 hereby certify in connection
with the Partnership's Quarterly Report on Form 10-Q for the period ended
September 30, 2003 as filed with the Securities and Exchange Commission (the
Report) on the date hereof, that:

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

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

Dated: November 13, 2003

                                     /s/ Ronald J. Turner
                                     -----------------------------------------
                                     Ronald J. Turner
                                     President and Chief Executive Officer
                                     TC PipeLines GP, Inc., as general partner
                                     of TC PipeLines, LP