Prince Harry was said to be "staggered" after seeing that he and his wife Meghan Markle were effectively being "airbrushed" from the Royal Family by his grandmother, the Queen, according to Tom Bower.
Bower is releasing a book titled Revenge: Meghan, Harry, and the War Between the Windsors later this month, and has cultivated, through interviews with various sources, an inside story of the Sussexes' departure from the Royal Family.
Though Meghan and Harry announced to the public that they would be stepping back as senior royals in January 2020, the decision had been in the works for months.
Bower claims Meghan "consulted with her Los Angeles team about the best terms for their departure from Britain," which coincided with "Prince Andrew's BBC TV Newsnight interview ".
This prompted the Queen to discuss a "slimmed down" monarchy, focusing instead on the Duke and Duchess of Cambridge, during her 2019 Christmas Day broadcast, Bower says.
He writes: "As Harry watched his grandmother from Vancouver, he was staggered. Four silver-framed family photographs had been carefully placed behind her.
"They showed the Queen's father George VI, Prince Philip, Charles and Camilla, and finally William and his family.
"To Harry's fury, there was no photographer of himself, Meghan, and Archie.
"The Windsors were airbrushing the Sussexes from history."
There has allegedly been longstanding tension between the couple and the Royal Family for several years, beginning in 2018 when it is suggested Prince Charles was angry at Harry and Meghan over Thomas Markle's comments in the media criticising the Royals.
The Prince of Wales reportedly demanded that Meghan "make him stop", but Meghan insisted she couldn't do so, frustrating Charles and the Queen.
This is just one of the many bombshell allegations made in Bower's book, which will be released on July 21.
Other allegations include that the Duchess of Sussex was "abrasive" to staff.
Bower previously told the Sussex couple that they should not expect to "silence" him over his book.