The Duke of Sussex has made several bombshell claims involving his sister-in-law the Princess of Wales in his new memoir.

In the controversial tell-all book Spare, which was leaked ahead of next week’s publication and also put on sale early in Spain, Harry has revealed intimately personal details about his life and family.

It comes ahead of Kate’s birthday on January 9 next week. Three years ago, on January 8 2020, Harry and Meghan released their first statement saying they were stepping back as senior royals.

Kensington Palace and Buckingham Palace have declined to comment, but the inflammatory claims are being seen as damaging Harry’s fragile relationship with his brother William – a future king – beyond repair.

Several revelations that have emerged so far involve William’s wife Kate.

William and Kate approved of Harry’s Nazi costume

Harry has claimed that William and Kate encouraged him to wear a Nazi uniform to a fancy dress party in 2005.

The duke, who was 20 years old at the time, made headlines when he wore the outfit to Olympic equestrian Richard Meade’s “native and colonial”-themed party, which William went to dressed in a lion costume.

“I phoned Willy and Kate, asked what they thought. Nazi uniform, they said,” he wrote, according to Page Six.

“They both howled. Worse than Willy’s leotard outfit! Way more ridiculous! Which, again, was the point.”

Meghan upset Kate over “baby brain” comments

Harry claims that Meghan upset Kate, then the Duchess of Cambridge, by saying she must have “baby brain” during a phone call in the run-up to the royal wedding in 2018, according to The Sun’s translation of a Spanish copy of the book.

In the book, Harry also writes that his wife apologised to Kate when the two couples met for a reconciliatory tea at Kensington Palace, saying that is how she speaks to her friends.

But William, then the Duke of Cambridge, “pointed a finger” at Meghan, saying: “Well, it’s rude, Meghan. These things are not done here,” to which she said: “If you don’t mind, keep your finger out of my face.”

The Telegraph also reported that Harry claims Kate, who had recently given birth to Louis, told Meghan: “You talked about my hormones. We are not close enough for you to talk about my hormones.”

Kate reluctantly lent Meghan her lip gloss

In his memoir, Harry recalls an “awkward moment” when his wife asked Kate to borrow some lip gloss ahead of their Royal Foundation Forum appearance in 2018, according to Page Six.

“Kate, taken aback, went into her handbag and reluctantly pulled out a small tube,” Harry writes.

“Meg squeezed some onto her finger and applied it to her lips. Kate grimaced.”

The duke wrote that the four “should’ve been able to laugh” about the moment but the press “sensed” it was “something bigger” and so Kate was “on edge” that she was now “going to be compared to, and forced to compete with, Meg”.

Sussexes offended by William and Kate switching place cards at wedding

Harry has admitted that he and Meghan were offended when William and Kate switched place cards and changed seats at their wedding, according to the Telegraph.

The duke writes that the couple had followed the American tradition of placing couples next to each other but William and Kate insisted spouses sit apart on their table.

Harry writes: “Had it really come to this? Shouting at each other about place cards and hormones?”

Kate made Meghan cry over bridesmaids’ dress fitting

In his memoir, the Duke of Sussex also writes about the infamous fight between Meghan and Kate during a bridesmaids’ dress fitting for Princess Charlotte.

Harry wrote that the Princess of Wales texted his wife the week of the wedding about a “problem” with Charlotte’s dress, according to Page Six.

Kate said Charlotte’s dress was “too big, long and baggy” and that the youngster “burst into tears when she tried it on”.

He wrote that the dresses, which were made by Givenchy’s then-creative director Clare Waight Keller, had been hand-sewn based solely on measurements so it made sense that they would need some tweaks.

But Kate allegedly said that the dress needed to be remade from scratch.

The duke claims Meghan told Kate to bring Charlotte to the palace where a tailor was waiting to perform alterations for all six of the bridesmaids and she eventually agreed.

Harry wrote that he later found Meghan in tears “on the floor” over the disagreement but the next day Kate apologised, bringing over flowers and a card.