Prince Harry has previously been rather disparaging about his stepmother Queen Camilla in his memoir Spare.

Queen Camilla is likely to be “otherwise engaged” when Prince Harry returns to the UK next week for the Invictus Games 10th anniversary commemorative service on May 8 – with these simple two words showing exactly how the Queen feels about her husband’s youngest son.

It is understood that Harry has extended an invitation to the service to other members of the Royal Family, but as it falls on the same day as a Buckingham Palace garden party it seems unlikely that many will attend.

There is a possibility that he may be able to meet with King Charles, but the Queen herself is not in a hurry to be reunited with her estranged stepson, according to an inside source.

They told the Daily Express: “Let’s just say that the Queen might be otherwise engaged. Although the King will have time in his diary for a brief visit, that hasn’t been confirmed yet due to the garden party schedule.

“Even if Harry does meet with his father, it is highly unlikely that Camilla will be in the same room.”

Royal Family at Trooping The Colour 2019

Queen Camilla is not likely to be reuniting with Prince Harry (Image: Getty)

Harry last visited the UK in early February, dashing over to be here for just one day after learning that the King had been diagnosed with cancer.

The two had a brief meeting at Clarence House in London, lasting less than 45 minutes, although it is not known whether Camilla was present.

The source added: “Harry did the right thing by flying over in February. But it was very much a last minute surprise and was somewhat forced upon the household.

“The optics wouldn’t have been good if a meeting didn’t take place at that time.”

Queen Camilla hosts reception and gives speech

The Queen has her own engagements to contend with (Image: Getty)

It is not expected that the Duke of Sussex will stay in London for long, as he and Meghan Markle have a trip to Nigeria planned for later in the month.

If he does manage to meet his father it will be a brief encounter thanks to the King’s packed schedule, which includes his weekly meeting with the Prime Minister as well as the garden party.

The source explained: “Health permitting, the King is due to attend the garden party at Buckingham Palace on May 8. If a meeting with Harry were to take place it would have to be just before or after that.”

King Charles laughs with Prince Harry

Charles and Harry in happier times (Image: Getty)

They added: “There won’t be any special arrangements made for a meeting, but one could be squeezed into plans already in place.”

Since his move to the US, the Duke has had a strained relationship with the rest of the Firm, with his and Meghan’s TV appearances and his book Spare further worsening relations.

The couple had become notorious for dishing the dirt on the Royal Family, however their latest projects with Netflix suggest they are moving onto a new chapter.

Meghan is launching a new cooking and lifestyle programme in conjunction with her new brand American Riviera Orchard, while Harry is making a new series about competitive polo.