Tory leader and Witney MP David Cameron surged ahead of the opposition when he took on runners racing a mile for Sport Relief.

Among the first to cross the finishing line, he stormed in leaving Olympic athletes Christine Ohuruogu and Colin Jackson trailing in his wake.

Slightly puffed, he turned to shake hands with the former world hurdle champion with a jubilant smile on his face.

As he caught his breath, he said: "It's lovely to have a few people cheering you on - it makes running a lot easier. It was very nice and it is the only time I have beaten Colin Jackson at anything."

Asked how his political rival Gordon Brown would have fared, he replied: "I don't know - he should have turned up."

Other famous faces taking part in the Sport Relief Mile along the Thames, in central London, included model Jodie Kidd, TV presenter Ben Fogle and DJ Jo Whiley.

They ran alongside thousands of Londoners raising money for poor and vulnerable people around the world.

Comedians Eddie Izzard paused during his run to shake hands with fellow competitor Major Phil Packer, who lost the use of both legs after a rocket attack in Basra.

More than 165,000 people are expected to complete sponsored walking and running events around the country.

The events follow a TV marathon on Friday night which raised more than £29 million for the charity.