U.S. President Barack Obama met Britain's Queen Elizabeth and her husband at Buckingham Palace on Tuesday. He is under a two-day state visit to keep the special relationship between United States and Britain.

Ceremonial cannon sounded 41 blasts when Obama and his wife arrived and he was treated to a tour of the palace portrait gallery and a wonderful state dinner with the Queen.

In the afternoon, Obama also played ping pong with British Prime Minister David Cameron and students at the Globe Academy in London.

This is the second stop of a four-nation European tour and on Thursday Obama will attend a G8 Summit in Deauville, France, and then conclude the tour by visiting Poland.

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