King Charles has been warned to "slow down" with working after receiving his cancer diagnosis, a royal author has claimed.
It has been announced that the king was diagnosed with "a form of cancer" but will still be performing some of his royal duties.
Speaking to GB News, Robert Hardman said: "None of us were expecting anything like this less than a year and a half into his reign when both of his parents lived to ripe old age.
"He's a keen walker, he doesn't eat or drink very much, he doesn't even eat lunch. So, we are all worried.
King Charles was diagnosed with cancer
GETTY"Yesterday afternoon rumours started swirling around and some of them were quite bleak. When we got the statement it was quite upbeat.
"It said that we're going to try and keep business as usual as much as we possibly can. Certainly, the constitutional side of his duties is unaffected.
"He's going to carry on with his meetings with ministers and the red boxes. The big difference is that he's having to cancel all his public engagements because his medical team doesn't want him going into crowded situations with strangers who may have germs or infections.
"So it's a practical, pragmatic response at the moment. There's certainly no sense of panic. There's no sense of any major change to any of the constitutional machinery.
Robert Hardman warned that The King will have to "slow down"
GB News
"There are mechanisms in place for when we have either an ill or an incapacitated monarch, but no one is dusting those off."
Hardman explained: "He just wants to get on with the job. He loves interaction with the public, he likes crowds, he likes walkabouts.
"One of the problems they normally have with him on the road is trying to keep him on time because just as he's going from one engagement to another, he'll see a crowd of people and pop over the road for a chat.
"One of Queen Camilla's great skills in these situations is she's about the only person who can give him a prod.
King Charles loves to work
X"She often uses the sharp corner of her handbag in the small of his back to remind him that it is time to move on.
"He enjoys meeting the public.
"He always has done, and that's going to be the greatest frustration. I'm not sure if he'll be the greatest patient.
"I imagine they are trying to ration the paperwork, the correspondence, the bump, the briefing notes that he likes receiving.
"One of his former aides said to me you could never put too much on his plate. He is used to working late pushing and himself and I think that's obviously going to have to slow down a bit and and somebody's got to tell him that.