Prince William was allegedly livid with Prince Harry on his wedding day for one specific reason and it didn't have anything to do with Meghan Markle.

The royal brothers have had a very public feud in recent years with their relationship deteriorating since Harry's shock exit from the Royal Family in 2020.

However, it seems things had been frosty between the two princes well before the duke's move to the US as William was reportedly left seething with his younger brother over his appearance on his wedding day to Meghan in 2018, the Mirror reports.

Prince Harry chose to have a beard on the Sussexes' big day which he explains was a "clear violation of protocol" in his tell-all memoir Spare.

The Duke of Sussex claims he asked for the late Queen's permission to have facial hair before the ceremony but it was William who took offense to his actions.

Prince Harry, Duke of Sussex and Meghan, Duchess of Sussex wave from the Ascot Landau Carriage during their carriage procession on Castle Hill outside Windsor Castle in Windsor, on May 19, 2018 after their wedding ceremony.
Prince Harry chose to have a beard on his wedding day to Meghan Markle in 2018 which went against royal protocol

He wrote: "But then I explained it to my brother and he... bristled? Not the done thing, he said. Military rules, so forth.

"A beard was thought by some to be a clear violation of protocol and long-standing norms, especially since I was getting married in my Army uniform."

The 39-year-old prince claims he backed his decision by pointing to other royals who had also done the same thing like George V but William was furious that he had spoken to the former monarch about it.

Harry alleged his brother told him: "You put her in an uncomfortable position, Harold! She had no choice but to say yes".

When the Prince of Wales insisted that his younger brother should get rid of the beard as he had to shave off his own facial hair for his wedding to Kate in 2011, Harry felt that he had found the reason why his brother was so adamant about it.

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He said: "Ah, there it was. After he'd come back from an assignment with Special Forces, Willy was sporting a full beard, and someone told him to be a good boy, run along and shave it.

"He hated the idea of me enjoying a perk he'd been denied."

During a televised interview to promote Spare, he described his beard as “a shield to my anxiety” and that it made him feel like “the new Harry”.

Speaking to ITV's Tom Bradby, he said: “I think…there’s a level of competition there. I remembered that William had a beard himself and that Granny and other people, the ones to tell – told him that he had to shave it off.

Prince Harry and Prince William arrive at Westminster Abbey prior to his wedding with Kate Middleton in central London on April 29, 2011.
Prince Harry claims during his memoir that William was angry because he was forced to remove his facial hair for his own wedding day to Kate in 2011

"The difference for me, if there was a difference, but the difference for me was, as I explained to my grandmother, that this beard I’m still – that I’m still wearing, felt to me at the time like the new Harry. As almost like a shield to my anxiety.”

Regular appearances of Prince Harry on American television where he has been highly critical of the Royal Family had added to the friction between him and the Prince of Wales.

He made several bombshell claims in Spare about William including a physical confrontation that he alleges took place between him and the brother at Nottingham Cottage in Kensington Palace in 2019.

According to Harry, William called Meghan “difficult”, “rude” and “abrasive” which the duke said parroted “the press narrative” about his wife.

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