Queen Camilla was initially opposed to Prince William and Kate Middleton’s relationship, according to a royal expert.

Christopher Andersen, author of “The King: The Life of Charles III,” told Us Weekly in a new interview that Camilla, 77, didn’t like William, 42, and Middleton, 42, at first when they met and fell in love at St Andrew’s University in Scotland.

“Camilla’s a believer in aristocracy [and] kind of a snob,” Andersen said, adding that Camilla didn’t think Middleton “was of their class.”

He also claimed that William merely “tolerates” his stepmother, and that Camilla “has always been a little afraid of William.”

The alleged tension between William and Camilla was revealed by Prince Harry in his bombshell memoir, “Spare.”

In the book, Harry, 39, claimed he and his older brother “begged” their father, King Charles III, to not marry Camilla. He also accused Camilla of leaking stories to the press about him and the rest of the royal family.

“I remember wondering … if she would be cruel to me; if she would be like all the wicked stepmothers in the stories,” the Duke of Sussex wrote in his book.

Camilla infamously had an on-again/off-again affair with Charles, 75, while the former prince was married to the late Princess Diana throughout the 1980s and 1990s.

Diana died in a fiery car crash in August 1997 and Charles, despite his sons’ concerns, tied the knot with Camilla in 2005.

“Despite Willy and me urging him not to, Pa was going ahead,” Harry wrote in his book about Charles and Camilla getting married.

“We pumped his hand, wished him well. No hard feelings. We recognized that he was finally going to be with the woman he loved, the woman he’d always loved,” Harry said.

In the Us Weekly story, a source noted that William and Camilla have “overcome” a lot in their relationship throughout the years.

“William and Harry had always distrusted Camilla and felt resentment toward her because of their devotion to their mother,” said the source. “They never felt comfortable opening up to her in any real way.”

However, the source noted that William “grew closer” to his stepmother after Harry left the royal family in 2020.

“William and Kate don’t want any extra drama or tension in the family — they have enough of that with Meghan [Markle] and Harry,” the insider explained.

The source also shared that Middleton — who currently has cancer, as does Charles — is the reason for Camilla and William’s mended relationship.

“She’s never been dismissive of Camilla and always treated her with kindness,” said the source, noting that both William and Middleton “like the fact that Camilla’s normal and makes Charles less stuffy.”

“Kate likes her because she brings a real-life relatability into the family. She’s not all about the courtiers waiting on hand and foot. Camilla’s real like Kate is,” the source added.

The Post has reached out to Buckingham Palace for comment.