(Adds CEO quote, change of CFO)
By Rod Nickel
May 29 (Reuters) - U.S. fertilizer company Mosaic Co said on Thursday that its chief executive Jim Prokopanko will take a leave of absence for surgery to treat his previously disclosed cancer.
The company's board named current Chief Financial Officer Larry Stranghoener as interim CEO, effective June 1.
"It is in Mosaic's best interest, and mine, that I focus on my health during the six- to eight-week period that my doctors tell me I should expect to be out of the office for surgery and recovery," Prokopanko said in a statement.
Mosaic Chairman Robert Lumpkins said he expected Prokopanko to return to the job full-time in summer.
Mosaic, the world's biggest producer of finished phosphate products, also said Stranghoener will retire at the end of the year and will be replaced in the CFO position on June 1 by Richard Mack, who is currently Mosaic's general counsel.
When Prokopanko returns as CEO in summer, Stranghoener will work as executive vice president of strategy and business development until his retirement at year-end. (Reporting by Rod Nickel in Winnipeg, Manitoba; editing by David Gregorio and G Crosse)