Prince William Urged Prince Harry to 'Cool the Relationship' With Meghan Markle Due to Their Fast-Paced Romance

Prince William struggled to embrace Meghan Markle during the early stages of her engagement to Prince Harry, and a new biography captures the tension between the Prince of Wales and the Duke of Sussex leading up to the 2018 royal wedding.

"William, still concerned by the match, even sought assurances from the Queen that his brother's bride-to-be would not wear any jewelry in the collection once worn by Diana, Princess of Wales, even though his wife Catherine had been allowed to wear some, which would be due to her rank," Robert Jobson wrote in Catherine, the Princess of Wales.

"Harry claimed that the goodwill from William and Catherine disappeared long before the build-up to his wedding," Jobson added. "William had confided to his brother that he believed it would be better to give Meghan more time to adjust to the royal way of life and suggested he cool the relationship."

Harry and Meghan first met in 2016, but William had reservations about his brother's then-girlfriend.

"Harry felt affronted and judged it to be an insult. As a direct result, his relationship with his brother deteriorated fast. According to Harry's book Spare, William physically attacked him," Jobson added.

Upon joining the royal fold, Jobson claimed the former actress "ignored the royal hierarchy." "She had not so much stepped on royal toes as stamped on them," Jobson penned.

"When Meghan, who had forgotten her lip gloss, asked to borrow Catherine's, the duchess was 'taken aback' but reluctantly handed it to her. According to Harry, she 'grimaced' after Meghan had squeezed some onto her finger and applied it to her lips," he continued.

Since relocating to the U.S., the tension between William and Harry has worsened, and some insiders wonder if they'll ever mend things. OK! previously reported Diana's former butler, Paul Burrell, discussed the rift in an interview.

“There is no room for any reconciliation now, they just don't trust him. He's worn away all the trust that they had in him," Burrell said on behalf of Slingo. "They can't invite him back into the fold because they know that when he gets back to America, he'll tell Meghan everything and then the rest of the world will know exactly what's happening."

"I think it’s very sad, as he's done it to himself. William doesn't trust him and we will not see him let back into his environment. Whilst they don't trust him, they can't invite him back," he added. "I just think it's a sad situation, but how do you resolve it? There's always somebody in a family to upset the family unit and somebody that you don't trust that you don't want to allow back in and Harry, is that person. It’s very sad. If his mother was alive, it just would not be happening."

Never miss a story — sign up for the OK! newsletter to stay up-to-date on the best of what OK! has to offer. It’s gossip too good to wait for!

Aside from their feud, Meghan and Harry are building careers in Hollywood, but Burrell doesn't envision them succeeding without their HRH status.

“Meghan and Harry have divorced themselves from the brand, which is the royal family," the reality star noted. "They've downgraded themselves."

"They are disassociating themselves with them because it ruins their brand," he shared. "To be associated with Meghan and Harry isn't the best thing, and would rather be associated with William and Kate, who stand for truth, who stand for duty, who stand for loyalty to the country."