Prince William "went ballistic" when he heard about bullying allegations made against Meghan Markle by staff at Kensington Palace, a royal author has said.
Robert Lacey, who wrote Battle of Brothers, has traced the rift between the brothers to a row between Harry and William after Meghan was accused of bullying in the royal household - something she has denied.
In a new extract of his book, ahead of its release in paperback, Lacey spoke to a friend of Prince William who recounted how the future king reacted when Jason Knauf presented a "dossier" of complaints about Meghan from palace aides.
Allegations of bullying surfaced in The Times in March, just before Harry and Meghan's interview with Oprah Winfrey aired in the US.
Meghan's team dismissed them as a "smear campaign". Yahoo UK contacted her team for a comment.
In the Winfrey interview, Harry said the tone in the royal household he shared with William changed after their successful Australia and New Zealand tour in autumn 2018, comparing Meghan to Diana, and her star quality, suggesting there was jealousy.
But Lacey has indicated the issue that split the household stemmed from the row the brothers had after Knauf, a long-term staff member of William and Kate's, revealed the complaints.
Lacey's book said: "Knauf described Meghan’s treatment of one aide as 'totally unacceptable . . . the duchess seems intent', he wrote, 'on always having someone in her sights'. Specifying another staff member, Knauf alleged Meghan had been bullying her as well, 'seeking to undermine her confidence'. His office had received 'report after report', he wrote, from people who had witnessed 'unacceptable behaviour' by Meghan towards this member of staff."
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He continued: "Prince William went ballistic when he heard the 'dossier of distress' that Knauf had gathered. We do not know whether the communications secretary brought his allegations directly to his boss or submitted them via Simon Case. What we do know is that the prince was astonished and horrified. He was instantly furious at what he heard."
Lacey said William's friend recalled how the prince called his brother as soon as he read the so-called dossier of complaints, and Harry "flared up in furious defence of his wife", before he "shut off his phone angrily".
Lacey also claims William felt Meghan was "following a plan" and said Kate was "wary of her from the start".
The result of the row was that William "threw Harry out" of the joint household they had set up together in 2009, under the banner of Kensington Palace.
Harry and Meghan moved to Windsor, and split their household, choosing the moniker of Sussex Royal.
Meghan's team hotly contested the suggestion she was a bully, questioning the timing of the allegations when they emerged shortly before their tell-all interview with Winfrey.
The latest extract of the Lacey book comes before her first interview as an author, to be given on Father's Day on NPR Weekend, as she discusses her book The Bench.
Meghan and Harry stepped back from royal work in March 2020, moving to California where they have subsequently set up Archewell, and signed deals with Spotify and Netflix.
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