January 5, 2023 | 5:39pm

Prince Harry isn’t afraid to hit below the belt — or above the shoulders.

In his forthcoming memoir, “Spare,” the royal discusses his relationship with older brother Prince William, whom he calls Willy — and even insults his looks.

Harry, 38, writes that he had a moment of bewilderment after grandfather Prince Philip’s funeral in 2021, when he realized that his older brother’s resemblance to their mother, Princess Diana, had faded with time.

“I looked at Willy, really looked at him, perhaps for the first time since we were little,” Harry recalls, calling out the Prince of Wales’ “familiar scowl” that “had always been the norm” during their interactions.

In another section, he called his brother’s thinning hair “alarming” and “more advanced than mine,” though William is only two years older.

The bombshell book, which will be officially released January 10, details plenty of strife between the siblings over the years, with Harry even calling the future king his “archnemesis.”

Prince Harry takes aim at his brother’s bald head in “Spare.”
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He also details a physical fight with William in 2019 at Nottingham Cottage over wife Meghan Markle, claiming William called the former “Suits” actress “difficult,” “rude” and “abrasive” before lunging at Harry to knock him to the floor.

Kate Middleton was not spared, either, with Harry recalling that he thought “goodbye” to his brother at their 2012 wedding. The Invictus Games founder also recounted the drama surrounding his own 2018 nuptials, including a blowup between Middleton and Markle over Princess Charlotte’s bridesmaid dress.

The palace told Page Six it would not be commenting on any allegations in the book.

The memoir details multiple anecdotes of strife, awkwardness and plain animosity between the brothers and their wives, Kate Middleton and Meghan Markle.
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