"PETULANT" Prince Harry must make the first move to heal his rift with William, a royal expert says.
Richard Fitzwilliams told The Sun that any rift is "undesirable", especially when people who are battling illness - such as King Charles and Catherine, Princess of Wales - are involved.
The Prince of Wales celebrated his 42nd birthday on Friday - the day after watching England's disappointing Euro 2024 draw against Denmark.
His wife Kate, also 42, has been receiving chemo for an undisclosed form of cancer since February. She made her own return to public life during Trooping the Colour on June 15.
Buckingham Palace revealed the King had cancer on February 6 after a prostate operation.
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Speaking about the possibility of reconciliation between the Sussexes and the Royal Family, Mr Fitzwilliams said: "You never know what may happen.
"And of course two senior royals, the King and the Princess of Wales, are seriously ill.
"So you have a situation with a huge question mark in the future, and we have no knowledge or idea of how the Sussexes are going to respond in the future equally.
"They can't attack the Royal Family at this time. Obviously it would be highly insensitive.
"I think it's abundantly clear that any rift is undesirable, and when individuals are ill who are involved in it, it makes it even more undesirable.
"If the Sussexes, in their public appearances, decided to say something nice about the Royal Family, something positive, I think that would be a step in the right direction.
"But in reality what you need is something private, something we don't know about."
Mr Fitzwilliams said it was up to Harry to instigate any efforts at reconciliation as he had done the most to harm the royals.
However, an insider told The Sun that Mr Fitzwilliams' perspective appears "somewhat one-sided", and it is important the recognise that "relationships are reciprocal".
They added that it would not be "entirely fair" to place the sole responsibility of mending the relationship on Harry and Meghan.
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The rift dates back a number of years, culminating in 'Megxit' - a term coined by The Sun.
When asked about the perspective that it might be constructive for the Prince of Wales to reach out, Mr Fitzwilliams said: "The problem with any rift is that it leads to deep mutual mistrust.
"Harry and Meghan were deeply unhappy as senior working members of the royal family. He believed they were due an apology for the way Meghan in particular was treated."
He added: "Given that they are not currently attacking the Royal Family and the idea of bridging the rift is in the air, of course this is welcome.
"However, give a thought to the damage caused by what happened from the interviews they gave in South Africa, on Oprah, on the Netflix documentary and in Spare and the interviews publicising it.
"Of course William was enraged. They made the Queen's last years very difficult. The King evicted them from Frogmore."
But he later added: "Time can heal things. Serious illness can certainly change things."
Mr Fitzwilliams also questioned what the future held for Harry and Meghan - and their relationship with the Royal Family.
He said: "So far as King Charles is concerned, I think he and William are absolutely one at the moment on how to deal with these Sussexes.
"The point is how the Sussexes want to deal with the Royal Family.
"In the weeks and months to come we will see, and we will monitor, because what future have they got?
"What do they want to do? Is it just Netflix? Does she want to go into politics? All these these questions."
Harry stepped down from the Royal Family four years ago and has since made a number of shocking allegations about William.
Their relationship has only worsened after the Sussexes made a number of accusations against the Royal Family in their Netflix docuseries.
Harry and William were last seen together at King Charles's Coronation last May but they were sat separately and the Duke made a quick escape.
