Trump to take lap at Washington IndyCar race

US President Donald Trump is expected to take a ceremonial lap in his armored limousine and wave the green flag at an IndyCar race through the streets of Washington this weekend.

Practice and qualifying sessions for the Freedom 250 Grand Prix are scheduled for Saturday, with the race due on Sunday.

The course will pass landmarks including the US Capitol and Smithsonian Museums. Organizers said 25 drivers will make 147 laps at speeds of up to 185 mph, or 298 kph.

Workers have welded down more than 200 manhole covers so the force from the cars does not tear them off. Thousands of spectators are expected along the route, and all spectators will pass through metal detectors.

The event is being managed by IndyCar organizers, who are footing the bill for the logistical challenge that has shut some of Washington's busiest roads for days.

The race is part of celebrations marking the 250th anniversary of the signing of the Declaration of Independence on July 4, 1776.