Celebrations were launched across London after the British capital won the right to host the 2012 Olympic Games ahead of fierce rivals Paris.

"We are taking home the biggest prize in sport. I am absolutely ecstatic, this is our moment," said London bid chief and double Olympic champion Sebastian Coe.

"It's just the most fantastic opportunity to do everything we ever dreamed of in British sport."

British Prime Minister Tony Blair hailed London's successful bid as a momentous day for the capital.

"It is a momentous day for London," he said.

"It was genuinely a team effort. (Bid leaders) Seb Coe and Keith Mills and the team were just awesome throughout. They were just brilliant.

"I've never seen as good an operation in anything I've been involved in as that.

"I couldn't bear to watch (the final announcement).

"It is not often in this job that you get to punch the air and do a little jig and embrace the person standing next to you."

Olympic athletes joined in the celebrating, throwing their arms in the air in delight and hugging each other in London's Trafalgar Square as they watched the announcement in Singapore on a huge screen.

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