Prince Charles has vowed to keep the door open to his son with the breakdown of his relationship to Diana in mind, it has been reported.
Earlier this week Prince Harry and Meghan Markle made a secretive stop-off in Windsor while travelling from the US to the Netherlands for the Invictus Games.
It was revealed after the event that the couple had also met with the Queen, who has yet to meet their daughter Lilibet.
They also saw Charles and the Duchess of Cornwall for 15 minutes during their closely-guarded visit to Windsor Castle.
Charles and Camilla then left the castle together for St George’s Chapel, having met with Harry in person amid claims they've barely spoken in recent months.
The rift between Charles and Harry has become widely known, with the younger prince criticising his dad during an interview with Oprah Winfrey last year.
Harry told the chat show host that his father had not adequately supported him and also accused him of cutting him off financially.
Charles, who is said to be concerned about his younger son's memoirs which are due to be published later this year, was reportedly nervous about the meeting.
"He loves his son and he has been broken-hearted by everything that has taken place, although he fears history repeating itself with Harry just as it did with Princess Diana," a friend of Charles told Mail Online.
"But he also wants to keep the door open and keep talking, something he still regrets not doing with Diana."
At the end of last year Richard Kay, who was a personal friend of the Princess of Wales, suggested that the relationship of the royal father and son could have long-term, serious implications for the monarchy.
He was speaking after Harry made a veiled jibe about his father amid allegations of a cash-for-honours scandal that was engulfing his Charles's charity.
"Such a rebuke—especially if it continues—could have an impact on the Prince as monarch as we edge closer to his reign," Kay said of the criticism.
"And it is why this week those close to Charles are viewing the unraveling of the relationship between father and son as potentially as damaging as that between the Prince and Princess Diana."
If Kay is right, Charles' rift with Harry could prove an issue for the future king.
In 1991, while apparently happily married to Diana, Ipsos Mori polling showed 82% of Brits thought Charles would make a good king.
By 1996, the year of the divorce, he was down to 41%
That number now stands at 33%.
After meeting with Charles and Camilla, Harry and Meghan moved on to the Queen’s private apartment.
Senior royal sources have described the meetings as “incredibly warm and good natured” and “very cordial”.
The Duke and Duchess told Her Majesty they plan to return soon so the Queen can spend time with 11- month-old Lilibet and Archie, two, who are believed to be in the US.