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Jowell, London organizing committee chief Sebastian Coe and other British officials met with Barcelona Mayor Jordi Hereu and got a guided tour of key sites from the city's chief architect, Josep Acebillo.

Hereu said the Olympics transformed Barcelona's social and economic landscape,effectively putting the city on the global map.

The 1992 Barcelona Games produced 4 billion pounds (US$7.6 billion) in investment, enabling the city to make infrastructure improvements in eight years that otherwise would have taken 50 years, Coe said.

The 2000 Sydney Games triggered an extra 2 billion pounds (US$3.8 billion) in tourist revenue between 1997 and 2001.

The London Olympics will be centered in the city's East End, where a run-down district is being regenerated into a huge park area.

"We are committed to planning the Games in tandem with the long-term needs and aspirations of the community," Coe said. "Our task now is to take the best of Barcelona and build upon it."

Preparations for the London Games have been hit by the recent resignation of the American engineer in charge of building the venues and reports the infrastructure budget could soar to more than 5 billion pounds (US$9.4 billion; euro3.5 billion).