Cheney to briefly assume powers of presidency

Vice President Dick Cheney

WASHINGTON (CNN) -- Vice President Dick Cheney plans to spend several hours at the White House Saturday, and during part of that time he is expected to assume the powers of the presidency while President Bush is sedated during a colonoscopy.

Cheney's schedule includes meetings on homeland security and national security issues as well as his daily intelligence briefing.

Administration officials said Cheney's meetings are vice presidential business and not related to the decision by Bush to temporarily transfer power.

It is not unusual for the vice president to spend several hours at the White House on Saturdays. But on this day, he has been told to expect to be the acting president of the United States for up to a few hours while Bush undergoes the procedure at Camp David.

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Bush announced the decision as he left for the presidential retreat Friday afternoon, saying doctors advised him to have the colonoscopy because the same test two years earlier had revealed that he had "benign polyps."

The test is a common procedure and considered the best for detecting colon cancer or other large intestine problems.

The president said he feels great and has had "no signs, no symptoms" of trouble.

White House physician Dr. Richard Tubbs said Bush is to be sedated because it puts patients more at ease during the procedure.