David Cameron, U.K. prime minister, speaks during a session on day two of the World Economic Forum (WEF) in Davos, Switzerland, on Thursday, Jan. 24, 2013. World leaders, influential executives, bankers and policy makers attend the 43rd annual meeting of the World Economic Forum in Davos, the five day event runs from Jan. 23-27. Photographer: Jason Alden/Bloomberg *** Local Caption *** David Cameron