How protocol is stopping King Charles from seeing his grandchildren during US tour

Royal Briefing is a new vodcast on nine.com.au discussing the biggest royal stories around the world. The first three episodes are available to watch now on YouTube.

With three days down and just one to go, the King's state visit to the US has been a resounding success in proving the power of the royal family's soft diplomacy.

But many royal watchers believe that amidst the triumph of Charles' mission to pour oil on troubled waters (he's been called the Trump Whisperer), there is a glaring oversight in the King's four-day itinerary.

Watch the video above.

It is the royal family's elephant in the room of sorts.

The king has travelled to the US for engagements in Washington D.C., New York City and Virginia alongside Queen Camilla.

But there are no plans for the monarch to see his California-based son Prince Harry or his two grandchildren, Prince Archie, six, and Princess Lilibet, four.

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Simply put, the King is on a state visit – the highest level of any foreign tour – with no time for family side trips.

For nine.com.au's entertainment editor Nicole Douglas, that excuse does not cut it.

"We have to remember that he is a 77-year-old man at the end of the day, he is not going to have all the time in the world to see his grandkids – he's had a cancer diagnosis," Douglas says in the latest episode of the new vodcast Royal Briefing.

"He's literally in the same country as them. How long is he going to be able to travel all this way to see them in their actual home and spend time with them?

"It would be a damn shame if he didn't [although] I can see he probably won't."

Nine.com.au's royal reporter Natalie Oliveri says a visit to Montecito, where the Duke and Duchess of Sussex and their children live, would be inappropriate during the king's state visit.

"Montecito is on the other side of the country [to where Charles and Camilla are on the east coast] and it would be a logistical nightmare for the king and queen to pop in to California," Oliveri says on Royal Briefing.

"[Perhaps] they could meet half way – Harry and Meghan could travel to the other side of America and have a private meeting [with the king]."

In Royal Briefing, Douglas and Oliveri discuss the king's tour so far which has been labelled the most significant mission of his reign as the monarch acts as a mediator of sorts between the US and UK, who have been at odds for months over several key global issues.

The king's state visit is bound by strict protocol, deadlines and very tight schedules. Every engagement is planned to the minute and free time is almost non-existent.

Duty comes first. Family, second.

Oliveri adds: "A lot of people will criticise the king for not seeing Harry and his grandchildren.

"[But] this is not an ordinary family."

Douglas disagrees.

"Charles the grandfather would absolutely love to see his grandchildren," she says.

"Charles the monarch knows it's probably not the right move. But it feels like a slap in the face for Harry."

Oliveri adds: "But that's his job. It's duty first, family second."

Watch the Royal Briefing vodcast in full on YouTube here