King Charles has made a "terrible mistake" in granting permission for Prince Harry and Meghan Markle's two children to become a prince and princess according to a royal expert.
The Duke and Duchess of Sussex announced that Prince Archie, now four and two-year-old Princess Lilibet would receive royal titles during their daughter's christening in California earlier this year.
The decision put an end to years of speculation over whether the two young royals, who are sixth and seventh in line to the throne, would use their official titles.
Tom Bower, author of Revenge: Megan, Harry and the War Between the Windsors, claims that the monarch should never have allowed it as it was a "terrible mistake" that could humiliate the monarchy.
Fans of the Firm were also shocked by the move, given that the Sussexes made their dramatic exit from the royal family back in January 2020, the Mirror reports.
The acclaimed royal biographer told Express US: "Harry and Meghan have undermined the monarchy and Charles has made a terrible mistake.
"He should have cut them off straight away. He should never have allowed their children to be made a prince and princess."
Mr Bower also insists that Prince Harry "shouldn't have been invited" to the King's coronation in May and instead believes that his royal relatives should have completely cut off their relationship with the Sussexes after their move to Montecito, California.
Relations went from bad to worse between Harry and Meghan and the Firm after their infamous bombshell interview with Oprah Winfrey in 2021.
During their explosive chat with the iconic talk show host, the Duchess of Sussex sensationally claimed that a member of the family was racist towards her.
When it seemed like things could not get more bleak between the two, Harry published his tell-all memoir Spare at the beginning of the year and upset his relationship with his brother Prince William even more with further allegations against him.
Tensions rose once again when the duke claimed that the Prince of Wales had physically attacked him and left him on the ground which is an allegation that William has not spoken about publicly.
According to polling, Harry and Meghan's popularity has continued to fall on both sides of the Atlantic while the release of their Netflix series last year resulted in even more bombshell allegations.
However, the Duke and Duchess' Netflix deal reportedly won't be coming to an end anytime soon which leaves the door open for more bombshell documentaries and revelations about life in the Royal Family.
Despite widespread rumours that their deal is in danger, Netflix has shut down speculation by confirming they have a strong connection with the couple.
A spokesperson said: "The bond with Archewell Productions is one we deeply value. Harry and Meghan launched Netflix's most spectacular documentary debut to date."
Get the latest celebrity gossip and telly news sent straight to your inbox. Sign up to our daily Showbiz newsletter here.