After the alleged altercation, the Duke of Sussex claims the Prince of Wales told him there was no need to tell Meghan about what had happened – but he did tell her eventually after she noticed “scrapes and bruises” on his back.

Prince Harry has claimed he was physically attacked by his brother William during a row over his marriage to Meghan Markle.

It is among several revelations in his new book Spare, in which it is alleged that the Prince of Wales grabbed his brother and ripped his necklace before knocking him to the floor.

Harry goes on to claim that William had called the American actress “difficult”, “rude” and “abrasive”.

“It all happened so fast. So very fast. 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,” Harry wrote in the book.

“I lay there for a moment, dazed, then got to my feet and told him to get out,” the excerpt continued.

The incident allegedly took place at Nottingham Cottage back in 2019 when Harry was living there and started when William arrived and complained about Meghan.

According to US website Page Six, in Prince Harry’s book there is also a claim that William and Kate helped him decide on his infamous Nazi uniform, which he wore to a party in 2005.

He has since described it as “one of the biggest mistakes in my life”.

Sky News has approached Buckingham Palace and Kensington Palace and both will not be commenting on the allegations.

Sky News’ royal correspondent Rhiannon Mills said that these are “very serious allegations”.

She said: “We know in 2019 that the relationship between the two brothers was falling apart, so it wasn’t unexpected to hear that they were not getting along then. But it is shocking to be given this much personal detail.

“In the past there have been criticisms of Harry that he has made damning allegations of racism within the palace or allegations that they have not taken Meghan’s mental health seriously enough and some suggestions that they haven’t gone far enough in naming specifics.

“It seems that Harry, in this book, is not holding back.”

You don’t need to tell Meg about this’

Harry writes that his brother was not being rational and they both started shouting at each other, exchanging insults, before William claimed he was trying to help.

“Are you serious? Help me? Sorry – is that what you call this? Helping me?,” Harry said.

His comment supposedly angered William, and the alleged altercation took place after he offered him a glass of water.

Harry added that William urged him to hit back, before leaving and then returning “looking regretful and apologised”.

When he left again, Harry said he “turned and called back: ‘You don’t need to tell Meg about this.’”