Prince Harry 'Hurt and Disappointed' About Not Seeing King Charles During UK Trip: Royal Expert (Exclusive)

Prince Harry isn't spending time with his family while across the pond.

The Duke of Sussex is currently in the UK for a ceremony to mark the 10-year anniversary of his Invictus Games, and despite having time in his schedule, he will not get an audience with his father, King Charles III, or brother Prince William during his visit.

"He hasn't got many other plans," royal expert Katie Nicholl told ET of the duke. "He was, of course, hoping to see his family. Possibly that's why the trip was three days... but as we now know, there will be no family meetings."

Likewise, no royal family members stepped out to attend Harry's event, which paints a stark contrast to when he launched the Games a decade ago.

"When you look at the inaugural Invictus Games back in 2014... he had support from his father and from Prince William," Nicholl said. "... You could see that wonderful closeness between Charles and his sons, and you could see how happy Harry was to have the support of his older brother."

"When you consider that this is the 10th anniversary, this felt a little flat, I think it's fair to say," she added. "He certainly cut a pretty lonely figure... He looked very much an outsider over here in Britain."

The lack of meeting is particularly of note, Nicholl said, as Harry and Charles were "spitting distance" from each other at separate events.

"I think certainly the fact that time hasn't been made over these three days for father and son to have some sort of meeting -- when you consider their last meeting was just about 30 or 40 minutes when Harry flew all the way from California to see his father -- certainly fuels that narrative of a rift.

Even so, Nicholl's sources say "that the king is very, very keen to get his relationship with his son back on track."

"He very much wants to be close to his son again and to see more of his grandchildren, who he's barely seen since they were born," Nicholl said of Harry and  Meghan Markle's kids Archie, 5, and Lilibet, 2.

Because of that, Nicholl said, "There is a sense of surprise that he hasn't made time to see his son."

The "fundamental issue" remains, however, as there's been "this breakdown of trust between Harry and the family," according to Nicholl.

"Clearly, there are still some pretty major trust issues and concerns on Charles' part that any private meetings or conversations that he has with his son may not stay private for long," she said. "I think Harry's going to have to work really quite hard to repair some of that trust before he's going to get a sort of privileged audience with his father."

Knowing that, Nicholl said that she believes "there is just a feeling of of disappointment, certainly on Harry's part, and genuine sadness that he hasn't got to see his father."

"When you take away the rift and who they are in terms of the royal family, they are a family, and Harry's gone through an awful lot since finding out his father's been diagnosed with cancer," Nicholl said. "He's all those miles away, understandably very worried about his papa, as he calls him, and he is here for three days. I think it was very much his hope that he'd get to see his father. I'm told he's rather hurt and quite disappointed that he hasn't had that opportunity."

An additional disappointment for Harry may come from the fact that, on Wednesday, Charles appointed William to be the Colonel-in-Chief of the Army Air Corps, a role the king held for 31 years. It was Harry, however, who served multiple tours in Afghanistan, serving in the very unit that William will be in charge of.

"I think many people will see that as a bit of a snub from the palace, and perhaps a little bit of a poke in the ribs to Prince Harry... He's been stripped of his right to wear his military uniform, and now his brother's taken over the role that... Harry certainly would have expected to come to him had he still been a working member of the royal family," Nicholl told ET. "I think the timing does feel poignant. I think it's probably another slap in the face for Prince Harry, and yet another reminder that he's very much out rather than in when it comes to the royal family."

With that in mind, Harry and Meghan aren't expected to be invited to June's Trooping the Colour.

"I think it's incredibly unlikely," Nicholl said. "They are not working members of the royal family. I think for the king that prestigious spot up on Buckingham Palace's balcony is reserved for working family members. I'm sure people will read a lot into the family rift. We know there's great distance between Harry and his family, but in terms of whether he has a right to be on that palace balcony, he lost that right when he stepped down as a working member of the firm."

Even so, Nicholl believes that Charles, who's currently battling cancer, will make an effort to see Harry and his family before the end of the year.

"Harry has said that he had hoped that, out of the adversity of his father's illness, he would reunify with the family. It's clearly very much his intention," she said. "My understanding is the king also wants to sort of rekindle his relationship with his son. He loves his son. He's a very forgiving man. I think he certainly wants to move on. While time hasn't been made available on this particular trip, it'll certainly be the king's hope that he will get to see Harry and his family at some point later this year."

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