The Queen will be reunited with senior members of the royal family for their first joint engagement since December.
The royals will attend a series of events, including the G7 Leaders reception at the Eden Project on Friday evening.
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Afterwards, Prince Charles will host a reception for the G7 Leaders and CEOs from the world’s largest companies to discuss how the private sector can work with governments to tackle the climate emergency. Prince William will also join his father at the event.
The senior royals at their last joint engagement in December 2020
Meanwhile, the Queen, Camilla and Kate will attend an event in celebration of The Big Lunch at the Eden Project, which will form part of next year's Platinum Jubilee events.
The Duchess of Cambridge will also team up with First Lady of the United States Dr Jill Biden for a joint engagement earlier in the day.
The Queen will host President Joe Biden and the First Lady at Windsor on Sunday
Friday's engagements at the G7 Summit will kick off a big weekend for Her Majesty, who will mark her official birthday at a scaled-down Trooping the Colour parade at Windsor Castle on Saturday.
The Queen will then host US President Joe Biden and the First Lady at her Berkshire royal residence on Sunday. The President will be welcomed to Windsor by the Queen with a Guard of Honour, followed by tea with the monarch at the castle.
The royal family paid tribute to the late Duke of Edinburgh on Thursday to mark what would have been Prince Philip's 100th birthday. Buckingham Palace shared a series of photos of the Queen receiving a rose named in her late husband's honour at Windsor Castle.
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