Prince Harry details physical attack from Prince William in his memoir, Spare: 'He knocked me to the floor'

Prince Harry has reportedly detailed a physical altercation he had with Prince William in his upcoming memoir, Spare.

According to The Guardian - who obtained a copy of the unreleased biography - The Duke of Sussex recounted a "physical attack" by the new Prince of Wales at his London home in 2019.

The publication claims the confrontation between Harry and William was over Meghan Markle. In the book, Harry says his brother described Meghan as "difficult", "rude" and "abrasive".

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Harry said the fight escalated, writing: "[William] grabbed me by the collar, ripping my necklace and… knocked me to the floor".

"He set down the water, called me another name, then came at me. It all happened so fast. So very fast," a passage from the book reportedly reads.

"He grabbed me by the collar, ripping my necklace, and he knocked me to the floor. I landed on the dog's bowl, which cracked under my back, the pieces cutting into me. I lay there for a moment, dazed, then got to my feet and told him to get out."

The duke said the altercation resulted in visible injury to his back. He also wrote that Meghan later noticed the "scrapes and bruises" on his back and he then confided in his wife about the attack.

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"She was terribly sad," Harry is said to have written about Meghan's reaction.

Harry said William later apologised for the "regretful" physical fight they had – but reportedly said: "I didn't attack you, Harold.'"

The Guardian was able to obtain a copy of Spare despite "stringent pre-launch security" around the book.

The shocking scenes described in the book, according to the UK publication, is one of several Harry is set to detail in his memoir. He recounts many private conversations had between himself and other members of the royal family.

Harry will also speak about his father, King Charles III, and his reaction to his rift within the royal family.

The duke recalled a meeting between himself, Charles and William after the funeral of Prince Philip in April, 2021.

"Please, boys," Harry quoted Charles. "Don't make my final years a misery."

Elsewhere in the book, The Guardian reports Harry writes resentfully about his role as the "spare" to his brother William's "heir".

Spare is set for a worldwide release on January 11.