She added: “Afterwards Prince Charles with Prince William will host @G7 leaders and global CEOs to discuss how the private sector can tackle climate change.
“The Queen the Duchess of Cornwall and Duchess of Cambridge will attend an event celebrating The Big Lunch, spearheaded by @edenproject.
“The Duchess of Cambridge and @FLOTUS @DrBiden will also get together for a joint engagement on Friday focusing on early childhood.”
The reception will be held at the Eden Project in a nod to the climate talks set to be discussed at the summit.
The announcement of the charm offensive by the Royal Family follows a meeting between the Prime Minister and US President Joe Biden to discuss Brexit and the Northern Ireland Protocol.
Mr Biden has been vocal over Boris Johnson’s handling of the Northern Ireland Protocol. Jake Sullivan, US national security adviser, warned the UK’s Brexit negotiator, Lord Frost, that he could inflame tensions in Northern Ireland if he does not compromise over border checks.
Following the meeting, Emmanuel Macron upset the “harmony” of the G7 after laying into Mr Johnson’s stance on the Protocol, claiming he was “not serious” and warned that “nothing is renegotiable”.
Since 1951, the Queen has met 13 US presidents and has attended five state dinners at the White House – more than any other head of state, according to the White House Historical Association.