Barack Obama and Michelle arrived at the Kensington Palace and met Prince William, Dutchess of Cambridge Kate Middleton and Prince Harry.
According to the pictures released by the Kensington Palace, Obama was seen crouching down to greet young George and shake hands with him. George was allowed to stay up past his bedtime for the visit and spent about 15 mintues with the guests.
George, who met Obamas in his pyjamas and a robe was more than glad to sit atop the rocking horse gifted to him by Barack Obama when he was born.
The Obamas were greeted by Queen Elizabeth II and Prince Philip on their arrival at the Windsor Castle. Prince Philip personally drove the President and the First Lady to their castle in his Range Rover.
Here are some pictures taken from Kensington Palace's Twitter account:
Prince George meets Barack Obama in his PJs
Prince George had a special visitor on Friday. Barack Obama met the young Prince at the Kensington Palace.
Prince George with his rocking horse
Prince George sat atop his rocking horse gifted by Barack Obama during his birth.
Kate Middleton and Prince George share a moment
Barack Obama also met Kate Middleton and Prince William.
Michelle Obama and Prince Harry have a word
Prince Harry also met Barack Obama and Michelle and had a word with both of them.
Prince William and Barack Obama speak to each other
Barack Obama and Michelle arrived at the Kensington Palace on Friday.