Britain's Prime Minister David Cameron gestures next to London Mayor Boris Johnson while viewing a parade of British Olympic and Paralympic athletes through London September 10, 2012. Tens of thousands of Britons took to the streets of London on Monday to welcome the stars of the Olympic and Paralympic Games and celebrate a summer of sport that surprised even the most optimistic by lifting the national mood.REUTERS/David Davies/POOL  (BRITAIN - Tags: SPORT OLYMPICS POLITICS CITYSPACE)
Britain's Prime Minister David Cameron gestures next to London Mayor Boris Johnson while viewing a parade of British Olympic and Paralympic athletes through London September 10, 2012. Tens of thousandShow more

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