King Charles is reportedly keen to make amends with his estranged son Prince Harry, but peace talks won’t be easy.

The claim was made by DailyMail contributor Robert Hardman, the author “The Making of a King: King Charles III and the Modern Monarchy”.

Hardman told Fox News Digital that the king, who is battling an undisclosed form of cancer, would only be willing to speak to the Duke of Sussex again once he felt his son was no longer airing his grievances publicly.

“People keep asking, ‘Could Harry get back into royal life?’ Could he do that? Could he do that?” You never say never with the royal family,” Hardman explained. “But I think a good starting point is to get back to a situation where it’s perfectly normal for Harry to visit the UK and see his father with the children (and) and Meghan (Markle) as well if he wants to.”

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Prince Harry has had a strained relationship with his family since stepping down from royal duties in 2020. (Isabel Infantes/Pool/AFP via Getty Images)

“It’s going to be a slow burn, yes, but no, the door isn’t slammed shut.”

— Robert Hardman, author of The Making of a King: King Charles III and the Modern Monarchy

“We … feel that she doesn’t like coming to the UK at all,” Hardman claimed of the Duchess of Sussex. “But if you get into a situation where they’re coming to see grandpa every once in a while — once that happens once or twice and it normalizes, they can start building from there.”

“It’s going to be a slow burn, yes, but no, the door isn’t slammed shut,” he added.

Hardman believes Harry should try to make peace with his father if he ever wants to return to the royal fold in any capacity. He described Prince William, heir to the British throne, as “very bold”, a royal who will prioritize the crown over his relationship with his younger brother, which is said to be non-existent today.

King Charles III and Queen Camilla wave as they board a Royal Australian Air Force plane through Faleolo International Airport following their visit to a farewell ceremony at Siumu Village in Apia, Samoa on Saturday. Buckingham Palace announced in February that the monarch had been diagnosed with an undisclosed form of cancer. (Chris Jackson/Pool/Getty Images)

“William is less radical than his father,” Hardman said. “They do things differently. They have their own different opinions on certain things… But they work as a team. It all comes back to the very night that Queen Elizabeth II died (in 2022) and the royal family gathered at Balmoral Castle. Everyone is sad when they eat dinner – except for Charles, (Queen) Camilla and William. They went to Charles’ place to determine what would happen next from that point on. They said to each other, “We have to be a team.”

Prince William is the heir to the British throne. His relationship with his younger brother Prince Harry is said to be non-existent. (Chris Jackson/Getty Images)

“Even in the years when Queen Elizabeth II was getting weaker and weaker and the king was taking on more duties, William felt he had to accelerate more and more,” Hardman continued. “That’s why William and Charles have a good working relationship… If you look back through history, there’s usually been a lot of tension between the monarch and the heir to the throne – really tremendous tensions… But that hasn’t happened in modern times .”

Queen Elizabeth II, England’s longest-serving monarch, died in September 2022 at the age of 96. (Dominic Lipinski/WPA Pool/Getty Images)

A source told royal expert Neil Sean that Harry has been feeling the “birthday blues” since turning 40. On September 30, the father-of-two attended the annual WellChild Awards in London, the charity he has continued to support since stepping down as a senior royal.

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Prince Harry, Duke of Sussex smiles as he attends the WellChild Awards 2024 at the Royal Lancaster Hotel in London on September 30. WellChild is a national charity supporting seriously ill children and their families. (Chris Jackson/Getty Images)

“Harry was keen to get an opinion on exactly where he is in the UK market and admitted to my source that he had birthday issues about turning 40, but added that he is excited for the next decade,” Sean told Fox News Digital. “The source described his reasoning as ‘basically nobody knows where life is going, right?’

The insider told Sean that the prince “… admitted he loves the WellChild Awards simply because it makes him rethink his life – whatever problems he thinks he has, it’s just nothing compared to what what are these brave children going through”. The source noted that Harry “misses the UK every day”.

The source claimed to Sean that Harry would consider returning to live in London full-time if it came to that, but “once you have kids, your life is no longer your own.”

The Duke and Duchess of Sussex have two young children – Prince Archie, 5, and Princess Lilibet, 3. They are grown in California.

Prince Harry has been the charity’s patron since 2007 and has attended the awards ceremony 12 times. (Yui Mok/PA Images via Getty Images)

“Later on in the conversation, he asked me if I’d had a chance to read his autobiography and if that changed my opinion of him,” Sean’s source said. “He seemed really keen on this particular line of questioning – it turns out I wasn’t the only one he said that to. When he left, he was still smiling, optimistic and positive”.

“I got the feeling that … his life wasn’t as fulfilling as he would like to portray it,” the source continued. “But we have to say that he made every one of those kids in that room at that hotel feel incredibly special, and for that, we should all be grateful.”

Sean believes Harry “wants to go back” to his home country, but the people he needs to convince are “his family – the royal family”.

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Sources have claimed to People magazine that King Charles has stopped returning Prince Harry’s calls and letters. (Chris Jackson/Getty Images)

Hardman previously claimed to Fox News Digital that Charles was urged not to answer Harry’s calls and texts to keep his “stress level down.”

“I know people keep saying, ‘Why doesn’t she see Harry when he’s in town?’ Why can’t I fix things?” Hardman explained, “But right now, there’s a sense that we have to keep the king’s stress level up. We don’t want him to have extra things to worry about. Let’s get over it… There’s a sense that now is probably not the time.”

“If you listen to what Harry has said in his TV series, in his book, in interviews — there’s a lot to unpack,” Hardman said. “There’s a lot of things he wants to go through to process them… At the moment, there’s a sense that it’s not the time. But I’m sure the king would like to normalize things.”

Robert Hardman’s book, The Making of a King: King Charles III and the Modern Monarchy, is available now. (Pegasus Cards)

A Buckingham Palace spokesman did not immediately respond to Fox News Digital’s request for comment.

Harry has had a strained relationship with his family since he and his wife she relinquished her royal duties in 2020. At the time, the couple said it was the intolerable intrusions and racist attitudes of the British media that led them to step down as members of the royal family.

“Spare” was published in January 2023. (Justin Tallis/AFP via Getty Images)

The father-of-two has since detailed his rocky relationship with his family in TV interviews, a documentary and his memoir, Spare.

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The Duke and Duchess of Sussex spoke to Oprah Winfrey in 2021, a year after their royal exit. (Getty Images)

In March 2021, Harry told Oprah Winfrey in a televised interview that the king stopped taking the phone calls shortly before he and his wife stepped down.

A friend of the couple told People magazine that safety had always been a primary concern for the prince, along with a lack of support from the palace.

In July, insiders told the press that Harry was preparing to appeal a court ruling that upheld the decision to deny him security. The Duke of Sussex wants to restore his security to allow more flexible visits to the UK for him, his wife and their two children.

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Sources claimed the issue plays a “crucial role” in Harry’s continued estrangement from his father.

Harry lost his taxpayer-funded personal security after giving up his status as a working member of the royal family.

“(They) didn’t feel like they had a choice,” the friend told the media. “The only option was to leave – for their sanity. I think they thought that if they got out of this bubble, there would be less focus on them.”

Prince Harry is seen here leaving in his chauffeured Range Rover after attending the WellChild Awards 2024 at the Royal Lancaster Hotel in London on September 30. (Max Mumby/Indigo/Getty Images)

According to the publication, some close to the palace have suggested that Harry’s memoirs and interviews have compromised the family’s trust in him. Meanwhile, those close to the prince argued that if he had adequate security, there would be no need for him to speak publicly to help pay.

If the security issue is resolved, “it’s swords down,” the friend claimed.

“(Nothing) would give (Harry) more happiness than being able to rekindle his connection with his father,” the friend told the outlet. “At the end of the day, you can’t undo bloodlines. He’s not asking his father for a nicer house or nicer cars. He’s asking because of the reality of the situation. He’s in danger.”