The King is ‘doing fine’ but ‘won’t slow down and won’t do what he’s told’, the Queen revealed on Saturday, as she opened up about the monarch’s health while he continues treatment for cancer.

Camilla provided the update on King Charles’s health to author Lee Child, who attended a reception ahead of his appearance at the Queen’s Reading Room Festival at Hampton Court Palace in Surrey.

The Jack Reacher writer, 69, wryly added: ‘Sounds to me like a typical husband.’

Charles recently returned to public-facing duties while still receiving treatment for an undisclosed form of cancer.

Also at the event on Saturday, actress Miriam Margolyes told the Queen ‘how much I love the King’.

The King is ‘doing fine’ but ‘won’t slow down and won’t do what he’s told’, Queen Camilla revealed at a reception for the Queen’s Reading Room Literary Festival at Hampton Court Palace on Saturday

She made the remarks to Jack Reacher author Lee Child, 69, who was appearing at the festival

Charles recently returned to public-facing duties while still receiving treatment for an undisclosed form of cancer. Pictured: The King and Queen mark D-Day in Ver-Sur-Mer, France

Speaking after she met Camilla on Saturday evening, Margolyes said the royal family has had ‘a hell of a time recently’.

She said: ‘I just told her how much I love the King, because I do.

‘He’s an absolute darling, and he’s brave as a lion and he’s warm and kind and he cares and they’ve had a hell of a time recently so I just wanted him to know that I love him very much.

‘She said she would tell him.’

Margolyes said she first met the King about 10 years ago and that she is ‘very fond of him’.

The actress added that she was ‘chuffed to b******’ to be at the Queen’s Reading Room Festival at Hampton Court Palace and it was ‘an incredible honour’.

Camilla’s candid update on the King’s health comes just days after his first public speech and most high-profile appearance since his cancer diagnosis.

On Wednesday, King Charles urged Britons not to forget the ‘service and sacrifice’ of the heroes of D-Day at a special event marking the historic date.

The monarch, 75, joined the Prince of Wales, leading UK politicians and veterans in Portsmouth to mark the 80th anniversary of the landings.

Actress Miriam Margolyes told Camilla ‘how much I love the King’ at Saturday’s reception

Queen Camilla spoke to actors, authors and supporters of literature at the event, including thriller writer Harlan Coben

Queen Camilla was spotted sitting next to her son, British food writer Tom Parker-Bowles

The pair seemed to enjoy the event, which was at Hampton Court Palace on Saturday

He told the crowd: ‘The stories of courage, resilience and solidarity we have heard today and throughout our lives cannot fail to move us, to inspire us and to remind us of what we owe to that great wartime generation.’

Charles, who received a standing ovation as he walked onto the stage accompanied by Queen Camilla, is understood to have been ‘adamant’ he would attend the commemorations as he continues his recovery from cancer.

On Thursday, King Charles was seen out and about again, where he told a D-Day veteran he is ‘doing well’ as he and Queen Camilla met heroes of the Normandy landings.

After attending the national commemorative event in Ver-sur-Mer today, Charles and Camilla visited a marquee where veterans had tea and cakes.

On one table, the King sat beside Ronald Hendrey, 98, of Clacton-on-Sea, Essex, who asked him about his health.

Mr Hendrey said: ‘He was very nice, he listened to what I was saying and took it in.

‘I asked him how he was doing, he told me he is doing well.’

King Charles is expected to take part in the upcoming Trooping the Colour ceremony, but will inspect the soldiers from a carriage rather than on horseback, it is understood.

He has previously taken part on horseback but it has been deemed prudent, given the length of the ceremony and the unpredictable weather, for him to be seated in an Ascot landau.

The monarch was recently given permission by his doctors to undertake more forward-facing public duties, although officials have stressed they need to carefully review each potential engagement, with adaptations made where necessary to prioritise his recovery.

Meanwhile, the Princess of Wales was unable to attend a planned military review ahead of Trooping the Colour as she ­continues to recover privately following her cancer diagnosis.

Camilla’s candid update on the King’s health comes just days after his first major public appearances since his cancer diagnosis, including a D-Day commemoration in France

The event would have seen her take the salute as the new Colonel-in-Chief of the Irish Guards.

In a letter to the Irish Guards, who are presenting their colours to the King this year, the Princess of Wales apologised for her absence and said: ‘I hope I am able to represent you all very soon’.

Elsewhere at the Queen’s Reading Room Festival, Child addressed the audience and spoke about how indebted he is to his female readers, who make up an estimated 65 per cent of buyers of his Jack Reacher books.

He told the audience: ‘I think you go into it imagining that women readers are going to want something more soft and human but the reverse is absolutely true and it’s an age thing as well… the most fearsome readers are older ladies.

‘I call them the killer grannies.

‘They absolutely love the mayhem and the blood and the broken bones and all of that, which took me by surprise, really… Reacher… wouldn’t think of himself as specifically a feminist, but he would regard himself as a rational human being.

‘And that makes you a feminist, in my opinion, that if you look at the world, like it really is, you see people as completely equal until proven otherwise.’

Child, whose real name is Jim Grant, said his series is post-feminism as it does not matter if the bad guy is male or female because the lead character, a former US army officer, ‘will break their neck’.

‘Male readers are so frustrating because there’s a huge demographic of men that are, first of all, rich enough to afford to buy books, and secondly, literate enough to read them,’ he added.

‘But they have a terrible bias against fiction.

‘They prefer to read about some president who died 200 years ago and so getting through to those people is difficult.’

The Coventry-born writer also said he sets his books in America as he can take advantage of scale of the country, such as in Die Trying, which sees Reacher ‘thrown into a van and driven 1,500 miles to a remote mountain hideout’ while still being in the US.

He added: ‘What really attracted me to writing about America was, as I say, the audience, they’re very into crime fiction, they’re into thrillers, they will take a chance.

‘And Britain is much more reserved about taking the chance on new things I find.’

Camilla spoke to actors, authors and supporters of literature at a reception for the festival on Saturday, including Helena Bonham Carter, Harlan Coben and Ian Rankin.

She was also spotted engaging with her son, British food writer Tom Parker-Bowles.