Listed: TSX, NYSE Symbol: POT SASKATOON, SK, Sept. 22 /PRNewswire-FirstCall/ -- Potash Corporation of Saskatchewan Inc. (PotashCorp) today announced that its Board of Directors has approved, subject to regulatory approval, an increase in the number of common shares sought under the company's current open market repurchase program. This amendment will allow PotashCorp to repurchase up to 4.0 million additional common shares, raising the ceiling from the initial maximum of 5.5 million, or 5 percent of the total number of outstanding common shares, announced in January 2005. The open market repurchase program, as amended, will terminate with the completion of the purchases, or no later than February 14, 2006. The share buyback will involve the purchase of common shares at the prevailing market price from time to time. All common shares purchased under the program will be cancelled. "At PotashCorp, we believe in reinvesting our ample free cash flow into our core potash business," said Bill Doyle, President and CEO. "The power of our long-term 'potash-first' strategy is evident. We view our business as undervalued and see an opportunity to buy back shares for the benefit of our continuing shareholders." Potash Corporation of Saskatchewan Inc. is the world's largest fertilizer enterprise producing the three primary plant nutrients and a leading supplier to three distinct market categories: agriculture, with the largest capacity in the world in potash, third largest in phosphate and fourth largest in nitrogen; animal nutrition, with the world's largest capacity in phosphate feed ingredients; and industrial chemicals, as the largest global producer of industrial nitrogen products and one of only three North American suppliers of industrial phosphates. This release contains forward-looking statements, which involve risks and uncertainties, including those referred to in the company's annual report to shareholders for 2004 and in filings with the U.S. Securities and Exchange Commission and Canadian provincial securities commissions. A number of factors could cause actual results to differ materially from those in the forward- looking statements, including, but not limited to: fluctuation in supply and demand in fertilizer, sulfur, transportation and petrochemical markets; changes in competitive pressures, including pricing pressures; risks associated with natural gas and other hedging activities; changes in capital markets; changes in currency and exchange rates; unexpected geological or environmental conditions; and government policy changes. DATASOURCE: Potash Corporation of Saskatchewan Inc. CONTACT: Betty-Ann Heggie, Senior Vice President, Corporate Relations, Phone: (306) 933-8521, Fax: (306) 933-8844, E-mail: , Web Site: http://www.potashcorp.com/

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