Leaders and Heads of State pose with Britain's Queen Elizabeth for a group photograph at Buckingham Palace in London April 1, 2009.(Xinhua/Reuters Photo)

British Queen Elizabeth II (R Front) talks with German Chancellor Angela Merkel during a reception hosted by the queen for leaders of the Group of 20 Countries (G20) at Buckingham Palace in London April 1, 2009. The G20 Summit on Financial Markets and World Economy will be held in London on April 2. (Xinhua Photo)