If Prince Harry and Meghan Markle continue to do this one thing, their golden days in the United States – or even around the world – may be over.

According to a renowned public relations expert, the Duke and Duchess of Sussex may "risk losing America" if they continue to assault and make accusations against the royals after Queen Elizabeth II's death.

In the aftermath of the sovereign's death, the former "Suits" star has lately postponed the broadcast of her "Archetypes" podcast for the next six weeks and even canceled her appearance on "The Tonight Show Starring Jimmy Fallon."

Instead, Prince Harry and Meghan will attend the royal family vigil at Westminster Hall alongside Prince William and Princess Kate Middleton, as part of the "current truce" between the Fab Four.

According to Martin Townsend, a senior PR adviser partner at Pagefield, sympathy for the British royal family is at an all-time high - so he stressed that the Duke and Duchess of Sussex should avoid any criticism while everybody is in mourning.

Speaking to The Telegraph, the expert said that King Charles III is now the new head of the monarch and therefore, can automatically command much more support than he used to.

The support has reportedly increased because of the heart-warming way he led an entire nation in mourning.

Pagefield explained that if Prince Harry and Meghan Markle chose to attack "all of that" at the moment, he believes that they are going to look "completely out of step."

"The couple's problem, though, appears to be that they can only acquire exposure for their salvos against the royals." What will they have left when that stops? "

READ ALSO: King Charles III Gains Criticisms For Being 'Fussy' In Viral 'Pen' Video But Fans Rush To His Defense

Many sources stated that Prince Harry's long-awaited book, which was ghostwritten by Pulitzer Prize winner J.R. Following the unfortunate death of Queen Elizabeth II, Moehringer has been completely canceled.

However, the autobiography, which included personal memories, was previously filed and authorized by attorneys.

Furthermore, the couple's interview with Oprah Winfrey last year reportedly irritated Prince William and Kate Middleton.

According to a source close to the Prince and Princess of Wales, they believe Oprah crossed a boundary and that someone should be held accountable for the "motives" behind it as well as "the grief it caused."

"They believe they've got to be steely to send a message that you can't just say this tremendously unpleasant stuff without their being consequences," the insider continued.

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