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                                                                    Exhibit 99.1

                            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 of Southern Peru Copper Corporation
(the "Company") on Form 10-Q/A for the period ending March 31, 2002 as filed
with the Securities and Exchange Commission on the date hereof (the
"Report"), I, German Larrea Mota-Velasco, Chief Executive Officer of the
Company, certify, pursuant to 18 U.S.C. (S) 1350, as adopted pursuant to (S)
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/ German Larrea Mota-Velasco
                                             ------------------------------
Date: August 14, 2002                        German Larrea Mota-Velasco
                                              Chief Executive Officer