US President Barack Obama is to make a state visit to the UK in May after accepting an invitation from the Queen, Buckingham Palace announced tonight.
Mr Obama will be joined by his wife Michelle for the three-day trip, which comes ahead of the G8 summit of world leaders in France which the American politician is expected to attend.
The announcement of the visit, from May 24 to 26, was made simultaneously on both sides of the Atlantic by the Palace and the White House.
Downing Street said: "We are very pleased that this visit is taking place. It is a sign of the strong and enduring relationship between our two countries."
It will be the first state visit by a US leader since George Bush came to the UK in November 2003, although Mr Bush was later hosted by the Queen at Windsor Castle in 2008.
Mr Obama has previously been to London for the G20 summit in 2009.
The US leader is likely to bring a delegation with him and is expected to hold talks with Prime Minister David Cameron on a range of issues.
As is traditional with state visits, the President and his wife, who will stay at Buckingham Palace, will receive a full ceremonial welcome and a banquet will be held in his honour.
The visit comes too late for Prince William and Kate Middleton's wedding on April 29, although a guest list for the ceremony has yet to be released.
Since the Queen came to the throne in 1952 there have been 12 US presidents and she has met every one except Lyndon B Johnson who took over after the assassination of John F Kennedy in 1963.
It was during Mr Obama's visit to London in April 2009 that she and the American First Lady formed a strong friendship.
After a photocall for G20 leaders at Buckingham Palace they were seen putting their arms around each other.
It was a breach of protocol but the pair seemed at ease.
Mrs Obama returned to Britain later that year with her daughters, Sasha and Malia, for a short private visit to the capital.
They were given a guided tour of Buckingham Palace and its gardens by palace staff and met the Queen.
At the time the two women, who share an interest in the countryside, gardening and clothes, were said to have stayed in touch.
A White House spokesman said: "The White House is pleased to confirm that President and Mrs Obama have accepted the invitation of Her Majesty the Queen and will travel to the United Kingdom for a state visit on May 24 through to 26 of this year.
"This trip will be President Obama's first European state visit, a sign of the strength of the special relationship between our two countries and the United States's enduring commitment to its European and Nato allies and partners.
"Further details of the trip will be made available at a later time."