The duke has travelled to London to mark the 10th anniversary of his Paralympic-style tournament for wounded veterans and serving military.

Griffiths questioned how “difficult” Harry made it for his father.

Charlotte Griffiths says Harry made ‘certain demands’

“There is some talk that behind the scenes, a lot of negotiating went on”, she said.

“I think the reason was because Harry made certain demands about who could be in the room and who couldn’t.

“Although on the surface it looks like a snub, Harry made it very difficult for his father.”

Asked to elaborate on the “certain demands”, Griffiths said “other forces” could have driven Charles’s thinking.

“Maybe other forces were driving Charles’s position on this”, she said.

“William may have had a thought about how this meeting should be conducted or whether it should be conducted at all.

King Charles is currently having treatment for cancerGetty“We know that Charles likes to meet Harry with Camilla in the room which isn’t always a popular decision.

“Harry was without his wife as well, so this was fraught with difficulty.”

A spokesperson for the duke said: “In response to the many inquiries and continued speculation on whether or not the duke will meet with his father while in the UK this week, it unfortunately will not be possible due to His Majesty’s full programme.

“The duke of course is understanding of his father’s diary of commitments and various other priorities and hopes to see him soon.”

Harry and Charles have had their differences in recent years after the duke stepped down as a working royal.

But after a meeting in February, Harry suggested the King’s cancer diagnosis could lead to a reconciliation.

In a Good Morning America interview, it was suggested a family illness could have a “reunifying effect”, and when Harry was asked “Is that possible in this case?” he replied: “Yeah, I’m sure.”