London becomes the first city in history to host three Olympics after it beat off Paris in the final vote for the 2012 Games held by International Olympic Committee (IOC) delegates at the IOC Session in Singapore Wednesday.
The British capital took the decision by just four votes, 54-50. London has held the Games on two previous occasions - in 1908 and 1948.
Paris, which hosted the event in 1900 and 1924, was making its third attempt in 20 years after defeats for the 1992 and 2008 Olympics.
A contract was signed between IOC President, Jacques Rogge, and London bid organisers, officially establishing London as the 2012 host.
"London and the IOC are the winners," Rogge said. "We are very pleased with the high quality bid."
"We know the cruelty of sport. There is only one gold medal." He urged as many of the losing cities as possible to come back and try again, using London as an example of repeated bids.
Sebastian Coe, London bid leader and double Olympic gold medalist, said, "I'm so grateful. Turning to Rogge he said, "We won't let you down. We want to transform the face of British sport."
Coe recalled when he was competing, there was a desire to encourage youth. "But this is an entirely different planet," he added, referring to the opportunity to have a vast impact.
Princess Anne said the result "was amazing".
"We always knew it would be close," she said, adding that the Royal Family had every confidence in the team for the future.
World 110m hurdles record holder Colin Jackson, part of the British delegation, said, "The whole nation has got behind us."
He attributed London's win to its emphasis on youth. The Games "will rejuvenate the East End," a depressed area. "It will change the whole feel" of the area. He said he was going to celebrate with champagne.
"I haven't much hair or I would let it down," he quipped.
Meanwhile, a French Chamber of Commerce function was plunged into gloom. Drinks were still being poured, but the atmosphere was bleak.
Jacky Depomed, president, said, "We are so disappointed. We were hoping so much. We do not understand."
In the shopping centre next to the convention centre, the huge crowd of Singaporeans and visitors who gathered gasped, clearing expecting a Paris victory.
Delegates from losing cities have not emerged from their different hotels yet.
As expected, Moscow was the first city to be eliminated, and the Russian capital was quickly followed by New York. Madrid was then eliminated in the third round, leaving just London and Paris.
A fourth round of voting then took place with IOC President, Jacques Rogge, declaring London the winner.
Prior to making their votes, the IOC members listened to one-hour presentations from the five cities and were presented with a final evaluation report.