The US is hosting William's Earthshot Prize in 2022 meaning the Duke and Duchess of Cambridge are likely to travel across the pond for the event. It comes as the Duke of Sussex, who quit royal duties with Meghan Markle for a new life in California, is set to release a book about his life.

       The Sunday Times' royal editor Roya Nikkhah predicted William and Kate will arrange a tour around the Earthshot Prize awards ceremony.

       And Ms Nikkhah added that the timing was "interesting" as Harry releases his tell-all memoirs.

       Ms Nikkhah told True Royalty TV's The Royal Beat: "I suspect there may well be a bit of a US tour from The Cambridges to put around [the ceremony], which will be very interesting in the year of Harry releasing his memoirs, which will be big news around the world, particularly in America."

       A source also said a US visit by the Cambridges is "very much on the cards".

       They told Vanity Fair's Katie Nicholl: "Team Cambridge is very focused on America and making sure they have a high profile over there.

       "The possibility of them making a high profile visit is very much on the cards for next year.

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