US President George W Bush had five polyps removed during a routine colon cancer test, which doctors described them as small and apparently not worrisome.

The polyps will be tested to determine whether there are any signs of cancer and the results are expected to be available within 48 hours to 72 hours, White House spokesman Scott Stanzel told reporters.

'He was in very good spirits and in good humor and looks forward to returning to his activities,' Stanzel said, adding that Bush was planning to take a bicycle ride later on Saturday after having lunch with senior aides.

Mr Bush, 61, transferred his presidential powers to Vice President Dick Cheney for just over two hours while he had the colonoscopy and recovered.

He was sedated during the 31-minute procedure which doctors performed at the presidential retreat in Camp David, Maryland.

Stanzel said that Cheney spent the morning reading at his home on the Chesapeake Bay in Maryland and 'nothing occurred that required him to take official action as acting president'.

The amendment has only been invoked twice before in US history, once by Bush in 2002 for the same procedure for just over two hours and once by then-President Ronald Reagan in July 1985 when he had colon cancer surgery.