Celebrities have been giving their own "good luck" messages to Team GB as the Olympics get under way.

Cheryl Cole said: "I want to wish Team Great Britain all the very best. I will be routing for every single one of you."

Amazing Spider-Man actor Andrew Garfield also contributed. He said: "Win or lose, it is how we play the game, just give it your all and you have my love and support."

But no London 2012 good luck message would be complete without the mayor of the host city.

"This is Boris Johnson wishing you every possible good luck. The whole country is behind you," he said.