Queen Elizabeth II dies — follow the latest news as the world mourns
Presidents, prime ministers and royals from around the globe came together as guests of the monarch for the event on Sunday evening.
The couple arrived in the presidential car known as The Beast in the middle of a convoy of vehicles at the back of the palace shortly before 6pm.
Members of the president’s entourage mingled with household staff and police next to the palace lawn while the reception took place inside.
Up to 250 leaders were invited, with most bringing their spouses, including France’s President Emmanuel Macron and his wife Brigitte.
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The Prince and Princess of Wales and other working members of the royal family including the Earl and Countess of Wessex, the Princess Royal and Vice Admiral Sir Tim Laurence, and the Duke and Duchess of Gloucester joined King Charles and Queen Consort Camilla in mingling with guests.
Dozens of leaders of Commonwealth countries and members of foreign ruling families also attended the reception.
At least 10 coaches arrived filled with guests who solemnly walked into the palace.
Some leaders were seen greeting each other while others remained silent as they walked up the steps.
Most of the guests were dressed in black, while some wore the traditional clothing of their countries.
European Commission President Ursula von der Leyen and president of the European Council Charles Michel arrived on coaches at the grand entrance.
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Brazilian President Jair Bolsonaro was also among guests at the event, which took place across the picture gallery, the white drawing room, the blue drawing room and the music room.
Guests arriving in their own vehicles and going through the Bow Room entrance at the back of the palace included the Bidens, UK Prime Minister Liz Truss, Foreign Secretary James Cleverly, and President of Israel Isaac Herzog.
They joined dozens of other dignitaries who went in the grand entrance at the front of the palace.
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The Emir of Qatar, Sheikh Tamim, arrived moments later.
World leaders and royals pay their respects to Queen Elizabeth II - video
Sultan Haitham of Oman was also seen arriving at the palace.