Barack Obama has described Prince George as "adorable" after the 2-year-old son of Prince William and Kate Middleton was allowed to stay up past his bed-time to meet the US President.
The Duke and Duchess of Cambridge hosted Obama and wife Michelle for an informal dinner at Kensington Palace in London last night, after which photographs were released of the guests kneeling down to shake hands with the young prince in his pyjamas.
"I guess you all know why I came this week. It's no secret. Nothing was going to stop me from wishing happy birthday to her majesty, or meeting George, who was adorable," he told audience gathered for a town-hall style event in central London today.
Obama began his day with a visit to the famous Globe Theatre in London to join in commemorations to mark the 400th anniversary of William Shakespeare's death. The playwright's works are being celebrated throughout the UK.
The theatre is a replica of the circular, open-air playhouse that Shakespeare designed in 1599.
Obama watched a brief performance of a portion of "Hamlet", including the famous "To be or not to be" soliloquy.
Dominic Dromgoole, artistic director of Shakespeare's Globe, said: "At the end of an extraordinary journey all around the world, it is great to return home to the Globe, and to be able to perform a few scenes and to be welcomed back by President Barack Obama.
"The spirit of 'Yes we can' has informed the entire tour, and it's an honour to meet the man who coined the phrase, and who exemplifies its spirit."
Addressing young people at the town hall event later, Obama's message was: "Take a longer, more optimistic view of history. If any of you begin to work on an issue that you care deeply about, don't be disappointed if a year out things haven't been completely solved.
"Don't give up and succumb to cynicism if after five years poverty has not been eradicated and we haven't resolved all of the steps we need to take to reverse climate change."
Referring to his legacy as US President, he added: "I'll look at a scorecard at the end... I think that I have been true to myself."