LONDON, ENGLAND - JULY 26:  Mitt Romney, the Republican nominee for the USA presidential election, leaves 10 Downing Street after meeting with British Prime Minister David Cameron on July 26, 2012 in London, England. Mr Romney is meeting various leaders, past and present, on his visit to the UK, including Tony Blair, Ed Miliband and Nick Clegg.  (Photo by Oli Scarff/Getty Images)