Many of the performers seemed equally excited by the games coming to London.

“I’m London born and bred and I think it will do really big things for the city,” singer Sophie Ellis Bextor said after singing James Bond theme “Nobody Does It Better” over a backdrop of images depicting Britain’s 19 gold-medal successes from Beijing.

As a beaming Johnson waved the huge flag, 650 buildings across Britain, including local government offices, raised handover flags of their own to mark London becoming the Olympic city. Another 80 flags were raised in British sites, such as embassies, around the world.

British cyclist Bradley Wiggins, who won two gold medals in Beijing, said the mood created by Britain finishing fourth in the medal table had helped contribute to a party atmosphere. “When I left, it was all ‘recession, recession, recession’ and we’ve come back to a country overwhelmed by Olympic success,” Wiggins said.

Phelps and Wiggins were cheered on stage, but some of the biggest cheers from the London crowd didn’t have anything to do with what was unfolding in their own Olympic city.

They were reserved for Beckham’s appearance in Beijing. “The eyes of the world have been on Beijing for the last two weeks as they have staged one of the most spectacular and uplifting Olympic Games ever,” London 2012 deputy chairman Keith Mills said. “For a short amount of time today, however, the world stopped and considered what’s coming next.”