A Buckingham Palace guard slipped in front of hundreds of tourists as he took up position in his sentry box.

The Queen's Guard was left red-faced as he slipped on a manhole cover during the famous Changing of the Guard.

He lost his footing and slid sideways, knocked his bearskin on the side of the box and dropped his rifle.

The soldier quickly scrambled to his feet as his colleagues marched past as if nothing had happened.

Footage of the mishap has been uploaded on Youtube.