US President George Bush fell off his mountain bike while completing the 25-kilometre stretch of a 27-kilometre biking course on his Crawford, Texas ranch.

White House spokesperson Trent Duffy said Bush was treated for injuries to his chin, upper lip, right hand and both knees.

Presidential physician Dr Richard Tubb attended to the wounds and declared Bush was fine.

The US president is expected to make a major televised speech on Monday night concerning his strategy for the 30 June handover to Iraqi sovereignty.