US President Barack Obama has hosted a dinner in honour of the Queen at the end of his state visit to the UK.
The president and his wife Michelle organised the intimate evening as a thank-you to the Queen for Tuesday's state banquet at Buckingham Palace.
It was held in London at the official home of the US ambassador to Britain.
Oscar winners Tom Hanks and Colin Firth, England footballer David Beckham and Harry Potter author JK Rowling were among the guests.
While the state banquet on Tuesday night had been a white-tie affair, the dress code for the Obamas' dinner was black tie.
The Queen and the Duke of Edinburgh were welcomed when they arrived by the Obamas. The two couples greeted each other warmly, shaking hands, and exchanging smiles and a few words before posing for the waiting international media.
The Queen wore an Angela Kelly white evening dress with gold and silver sequins, and an emerald necklace and matching earrings.
Mrs Obama was dressed in a black off-the-shoulder dress, and wore what appeared to be a diamond necklace and matching bracelet.
The two heads of state led the way through the residence's entrance, which was flanked by two US marines.
While the exact head count for the dinner is not known, the guests numbered more than 50.
They enjoyed a three-course meal that included lobster ravioli, griddled filet of aged Highland beef, crushed Jersey Royals with rosemary, asparagus and minted broad beans, topped off with classic pecan pie and brandy ice cream for dessert.
After the last plates had been cleared, American Tony Award-winning singer and actress Kristin Chenoweth performed for the diners.
The entertainer, who is also known for her television roles in The West Wing and Pushing Daisies, was also a guest at the state banquet.
Mr Obama is on a tour of Europe, which started in the Republic of Ireland, and is due to leave the UK on Thursday for the G8 summit in France.
Earlier on Wednesday, Mr Obama became the first US president to address members of both Houses of Parliament in Westminster Hall. He described the outlook for the world as challenging but said Britain and America had a vital role to play.
The Obamas went their separate ways on Wednesday afternoon, with the First Lady visiting Oxford University's Christ Church college, where she caught up with schoolgirls from Elizabeth Garrett Anderson school.
She first met pupils from the north London secondary school two years ago when she paid them a surprise visit during a trip to the capital with her husband.