Royal biographer Andrew Morton claimed that Prince William had something to do with Prince Harry and Meghan Markle's decision to leave the U.K. and move to America.

In the updated version of his book "Meghan and the Unmasking of the Monarchy," the author claimed that the Duke and Duchess of Sussex did not feel the support of the royal family, especially Prince William. Prince Harry felt that his brother did not reciprocate how he treated Kate Middleton during their relationship.

"He (Prince William) obviously had an influence in it," Morton alleged in his book according to Fox News. adding that Prince Harry "resented the fact that he supported his relationship with Kate Middleton over the years" and his brother questioned his relationship with Meghan Markle.

"We forget that the palace didn't believe she and William would marry. They didn't think she had what it took to be the future queen, initially. But Harry always supported her. He was always friendly with Catherine," the royal expert explained adding, "they were always joking and laughing together. And the fact that William couldn't do the same for him did not sit well with Harry. There's no doubt that there was a divide between the brothers."

Morton alleged that the Duke of Cambridge was cautious of Meghan Markle's Hollywood background and how it would impact the family. He felt "it was too quick" for his brother to marry someone he barely knew and "didn't know much about her family."

"He spent eight years with Kate and they broke up briefly at one point before they married. For Harry, it was instant when it came to Meghan...I remember in those early years, anything that was being reported about Meghan's family was coming from her brother and sister speaking out to the press."

The author of "Meghan: A Hollywood Princess" claimed that apart from Prince William, Prince Harry and Meghan Markle did not feel supported by other members of the family. Especially when the British press was out telling erroneous stories about her, including that she made Kate Middleton cry. She had to clear her name during her Oprah interview and reveal that the opposite happened.

Morton acknowledged that Prince Harry and Prince William are on different paths now. The Duke of Sussex reportedly does not have any regrets about moving to America where he can live a peaceful life with Meghan Markle and their two children.

Meghan Markle, Prince Harry and Prince William
Prince Harry last year revealed that he had grown apart from his older brother William Photo: AFP / Tolga AKMEN