King Charles is said to not be taking any of Prince Harry’s phone calls – and for one royal author, it’s easy to see why.
"When Harry branded his stepmother Camilla a ‘villain’ in his book and revealed that both he and William initially begged their father not to marry her, Harry committed what Charles regards as a cardinal sin," Christopher Andersen, author of "The King," told Fox News Digital.
"No one disses Camilla in royal circles and gets away with it – not even a son of the king," Andersen warned.
"When Harry branded his stepmother Camilla a ‘villain’ in his book and revealed that both he and William initially begged their father not to marry her, Harry committed what Charles regards as a cardinal sin."
Andersen’s statements came shortly after People magazine reported that the estrangement has worsened between the Duke of Sussex and the monarch, who is battling an undisclosed form of cancer.
According to the outlet, father and son had "a positive meeting" in February. However, their communication has since deteriorated. Those close to Harry, 39, claimed that the monarch, 75, isn’t taking any of his son’s calls or responding to his letters.
"He gets ‘unavailable right now,’" claimed a pal to the outlet. "His calls go unanswered. He has tried to reach out about the king's health, but those calls go unanswered, too."
The friend claimed there has been "complete silence" from the king.
Sources also told the outlet that Harry's brother, Prince William, has aligned with his father, making any hope for reconciliation "distant at best." Some palace insiders claimed to the outlet that Harry's memoir "Spare" and his public interviews have "compromised the family's trust in him."
Those close to Harry insisted that if the prince had proper security, which he lost after he stepped down as a senior royal in 2020, he wouldn't need to speak publicly in order to pay for it.
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Harry's pal said that once the security issue is resolved, it's "swords down."
A spokesperson for Buckingham Palace didn't immediately respond to Fox News Digital's request for comment.
Andersen said that Harry’s explosive memoir, which was published in 2023, was a major blow to his father.
"I think Charles could forgive Harry for some of the trouble he’s caused – including bailing on the monarchy … slamming his brother William for bullying behavior and suing for royal protection when visiting the U.K. But Charles is having a hard time forgiving Harry for taking what he sees as gratuitous potshots at his beloved Queen Camilla."
"This still remains a thorn on the king’s side," Andersen added.
In interviews to promote "Spare," Harry accused his stepmother of leaking private conversations to the media to burnish her own reputation. Harry also accused members of the royal family of getting "into bed with the devil" to gain favorable tabloid coverage, singling out Camilla’s efforts to rehabilitate her image with the British people after her longtime affair with his father.
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"That made her dangerous because of the connections that she was forging within the British press," he told CBS. "There was an open willingness on both sides to trade information. And with a family built on hierarchy, and with her on the way to being queen consort, there was gonna be people or bodies left in the street."
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The allegations about Camilla were particularly sensitive because of her role in the acrimonious breakdown of Charles’ marriage to the late Princess Diana, William and Harry’s mother.
Diana once described Camilla, who carried out a long-term affair with Charles, as the third person in their marriage. While many members of the public initially shunned Camilla, she has won fans by taking on a wide range of charitable activities and has been credited with helping Charles appear less stuffy and more in tune with modern Britain.
"Harry is obviously very concerned about his father’s cancer battle, and there is no doubt he would prefer to check in on the king more frequently," said Andersen. "But Camilla and others in Charles’ tight circle have convinced the king that it is not in his best interest to once again be sucked into the whole ‘Harry and Meghan mess.’ They want the king to focus on regaining his own health."
British broadcaster and photographer Helena Chard wondered whether palace aides are intervening to ensure that the king remains stress-free during his cancer treatments.
"King Charles does not carry a mobile phone," Chard claimed. "Maybe his staff have been fielding Prince Harry’s calls as… he brings unnecessary anxiety and drama into the royal family’s life."
"Without valuable royal family information, Harry will not have the content to give interviews," Chard claimed. "Thus, it makes sense that the king and his family may want to sever communication… Harry just needs to… bring some common sense to the table and take advice and guidance from the many people that want the best for him and his family."
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Harry has had a strained relationship with his family and has seen his father infrequently since he and his wife quit royal duties in 2020. At the time, the couple said the unbearable intrusions and racist attitudes of the British press were what had prompted them to step back as senior royals. The father of two has since detailed his rocky relationship with his family in TV interviews, a documentary and his memoir.
Harry's legal battle with his security following his exit started more than four years ago. The 39-year-old claimed he and his family were endangered when visiting his home country because of hostility towards him and his wife. Harry pointed out that the couple had been faced with ruthless hounding by the British news media.
In response, a government lawyer said Harry had been treated fairly and was still provided protection on some of his visits. The lawyer cited a security detail that guarded the prince in June 2021, when he was chased by photographers after attending an event with seriously ill children in west London.
In February, High Court Judge Peter Lane ruled that the panel’s decision, which provides for "bespoke" security on an as-needed basis, was not unlawful, irrational or unjustified.
The panel decision was made by the Royal and VIP Executive Committee. The group is made up of members of the royal family staff, the Metropolitan Police and several government offices.
Harry's pal told People magazine that nothing would give him "more happiness than being able to rekindle his bond with his father."
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"At the end of the day, you can't undo bloodlines," the friend told the outlet. "He's not asking his dad for a nicer house or nicer cars. He's asking because of the reality of the situation. He is at risk."
"There may well one day be rapprochement with his father," royal expert Hilary Fordwich told Fox News Digital.
"No father wants to lose a son," she shared. "The king is most disappointed, but not holding a grudge. He’s too busy with more important matters."
"He has never fallen out with Harry, he’s just mostly saddened," Fordwich claimed. "The king is not very happy with the direction nor way things have gone with Harry in general."
But peace talks between father and son may not happen anytime soon. People magazine also reported that the Duke and Duchess of Sussex were not invited to join the rest of the royal family at Balmoral Castle, their Scottish retreat.
The king is continuing Queen Elizabeth's tradition of heading to the estate during the late summer where other members of the royal family are expected to join him.
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The Duke and Duchess of Sussex have not been back to the U.K. with their children, Prince Archie and Princess Lilibet, since the late queen's Platinum Jubilee in 2022 amid the ongoing rift, the outlet shared. The couple have established a new life in California.
The Associated Press contributed to this report.