US President Joe Biden and First Lady Jill Biden have visited Westminster Hall to see the late Queen Elizabeth II lying in state.
SEE: Who will attend the Queen's funeral - see list of attendees
Biden and his wife were seen paying their respects to the late monarch on Sunday afternoon, ahead of joining King Charles III and Queen Consort Camilla at a special state event hosted at Buckingham Palace. Large crowds gathered at the barricades near Buckingham Palace and Parliament Square Garden as they arrived, joined by the US ambassador to the UK, Jane Hartley.
WATCH: Royal family deliver Queen's coffin to Westminster Hall
Biden then headed to Lancaster House to sign a book of condolence. He said: "To all the people of England, all the people of the United Kingdom, our hearts go out to you. You were fortunate to have had her for 70 years, we all were. The world is better for her."
MORE: 10 poignant photos of the royals in mourning dress - touching tradition revealed
He revealed the Queen reminded him of his own mother, explaining: "She had that look like, 'Are you OK? Anything I can do for you? What do you need?' And also 'make sure you do what you’re supposed to do.'
The US President added: "I have talked about how my mother and father thought that everyone, no matter who they were, no matter what their station, no matter where they are from, deserved to be treated with dignity. And that's exactly what she communicated – just the way she walked by her staff, just the way she acted.
US President Joe Biden and First Lady Jill Biden visited the Queen lying in state
"I think what she gave was a sense of, above all, the notion of service – we all owe something."
The president had also been due to meet Prime Minister Liz Truss on Sunday, but the talks were cancelled on Saturday. A "full bilateral meeting" was instead scheduled for Wednesday when the leaders are set to be in New York for the UN General Assembly.
Biden is just one of the world leaders expected at the Buckingham Palace reception this evening, with many of them also expected to visit the Queen's coffin en route to the event.
They paid their respects at Westminster Hall
As well as Canada's Prime Minister Justin Trudeau, Australia's Prime Minister Anthony Albanese and New Zealand's Prime Minister Jacinda Ardern, other Commonwealth leaders expected to attend include Bangladeshi Prime Minister Sheikh Hasina and Sri Lankan President Ranil Wickremesinghe. India will be represented by President Droupadi Murmu.
Among the attendees were over 30 members of overseas royalty, such as King Philippe and Queen Mathilde of Belgium and Prince Albert and Princess Charlene of Monaco, as well as world leaders including US President Joe Biden and French President Emmanuel Macron.
Biden signed the book of condolence at Lancaster House
On Monday, Charles will lead the nation in mourning for its longest reigning monarch at the state funeral for the Queen at Westminster Abbey.
TRIBUTE: Queen Consort shares moving tribute to the Queen: 'I will always remember her smile'
Two thousand people including international royals and world leaders will come together for a day of pageantry and military processions to remember the late Queen.
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