US president Barack Obama left Britain with a wide smile today following a highly successful state visit.
The American leader boarded Air Force One at Stansted Airport, Essex, turning to give a final wave from the steps of his Boeing 757 before taking off at 9.18am for Normandy, France, where he will attend a G8 group summit.
Mr Obama arrived at the airport at 8.59am in his helicopter, Marine One, and members of his entourage and American secret service officers were ready and waiting.
In blustery conditions, he was met by Lord Chamberlain Earl Peel, on behalf of the Queen.
At the foot of the aircraft steps, he was greeted by the American ambassador, Louis Susman and his wife Majorie, with whom the Obamas spent Monday night, along with Nicholas Jarrold, special representative for the Foreign Secretary.
Mr Obama kissed wife Michelle, in a plum-coloured dress and matching jacket, goodbye on the asphalt. The first lady will travel back to the US separately.
The couple, who arrived in London late on Monday evening, rounded off the visit by hosting a star-studded dinner last night in honour of the Queen.
They staged the black-tie event for the Queen and the Duke of Edinburgh as a thank you for Tuesday's state banquet at Buckingham Palace.
More than 50 guests, including David Cameron and wife Samantha, Hollywood actor Tom Hanks, Oscar-winner Colin Firth, England footballer David Beckham and Harry Potter author JK Rowling attended the dinner at Winfield House in Regent's Park, the official home of the US ambassador to Britain.
The Obamas warmly greeted the Queen and the Duke on the mansion's doorstep before the two heads of state led the way through the entrance of the residence, which serves a symbolic and political role and is a place where leading figures from all walks of life are entertained by America's official representative in the UK.
The Queen wore an Angela Kelly white evening dress with gold and silver sequins and an emerald necklace and matching earrings, while Mrs Obama was dressed in a black off-the-shoulder dress with a tight bodice. She accessorised her outfit with what appeared to be a diamond necklace and matching bracelet.
During the state visit, Mr Obama has taken pains to reaffirm the special relationship between the UK and the US.
Yesterday, he addressed the "mother of parliaments" at the 900-year-old Westminster Hall, where he declared that both countries "stand squarely on the side of those who long to be free".
Rejecting the argument that the rise of new economic powers such as China had sidelined Europe and America, the president insisted that "the time for our leadership is now".
He said Britain and America remained "indispensable to the goal of a century which is more peaceful, more prosperous and more just" at what he described as a "pivotal moment" in history, with demands for democracy across the Arab world and an international coalition fighting oppression in Libya.