WASHINGTON (Reuters) - Interior Secretary Ken Salazar is expected to announce he is stepping down, an Obama administration official confirmed on Wednesday.

The Denver Post, which first reported the move, said President Barack Obama had wanted Salazar to remain at the department, which has a key role in various industries such as energy and mining. It also oversees federal lands, including national parks and Indian tribal land.

Salazar is expected to leave the administration by the end of March to return to his ranch in Colorado, according to media reports.

It was not immediately clear who would replace the former U.S. senator, who took on the job in 2009. The post has typically been filled by someone from the West, where most of the federally-owned lands are.

Potential nominees include Jeff Bingaman of New Mexico, who just retired from the U.S. Senate where he was chairman of the Senate Energy Committee, and Christine Gregoire, the outgoing Democratic governor of Washington state.

Former Colorado Governor Bill Ritter, former North Dakota Senator Byron Dorgan, former Wyoming Governor Dave Freudenthal, and the recently departing Montana Governor Brian Schweitzer also are potential choices.

(This version of the story has been corrected to say Obama administration in first paragraph, not White House)

(Reporting by Steve Holland and Susan Heavey; Editing by Vicki Allen)