Exhibit 99.1


                                  CERTIFICATION
                 PURSUANT TO 18 UNITED STATES CODE SECTION 1350

      The undersigned hereby certifies that, to his knowledge, the Quarterly
Report on Form 10-Q for the fiscal quarter ended September 30, 2002 of Phelps
Dodge Corporation (the "Company") filed with the Securities and Exchange
Commission on the date hereof fully complies with the requirements of section
13(a) or 15(d) of the Securities Exchange Act of 1934 and that the information
contained in such report fairly presents, in all material respects, the
financial condition and results of operations of the Company.

                                        /s/ J. Steven Whisler
                                       ------------------------------------
                                        Name:  J. Steven Whisler
                                        Title: Chairman, President and
                                               Chief Executive Officer
                                        Date:  November 12, 2002