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Britain’s King Charles III was seen on Tuesday for the first time since the bombshell announcement of his cancer diagnosis, as questions swirl over the exact nature of his condition.

The unexpected disclosure from Buckingham Palace dropped on Monday evening. It revealed the monarch had already started treatment for an unspecified cancer that was identified while he was being treated separately for an enlarged prostate.

Charles, 75, is stepping away from public-facing duties during his outpatient treatment on the advice of doctors, but the palace stressed that he would continue state duties and paperwork.

“He remains wholly positive about his treatment and looks forward to returning to full public duty as soon as possible,” the palace said.

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King Charles and Queen Camilla are seen leaving Clarence House in London on February 6, the day after it was announced King Charles had been diagnosed with cancer.

It added that the King had opted to disclose his diagnosis “to prevent speculation and in the hope it may assist public understanding for all those around the world who are affected by cancer.”

While the British monarch has been unusually forthright about his health, much more so than his predecessors, the palace statement has triggered a storm of speculation and debate about exactly how much the public has a right to know.

The particular type of cancer was not revealed, and no further details are expected at this stage. Prostate cancer has been ruled out to CNN by a royal source, who did not provide any further detail.

UK Prime Minister Rishi Sunak Tuesday appeared to go further than the palace had while speaking to the BBC. Sunak said he was “like everyone else … shocked and sad” but that the King’s diagnosis had been “caught early.”

But when asked for clarification afterward, Sunak’s spokesman told reporters that the prime minister appeared to have been going off the palace statement, which noted “the swift intervention” of the King’s medical team.

CNN understands that Sunak was informed of the King’s condition prior to the public announcement – as were Charles’ siblings and children, whom he told personally.

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King Charles speaks with British Prime Minister Rishi Sunak during the opening ceremony of the World Climate Action Summit in Dubai, United Arab Emirates, on December 1, 2023. Chris Jackson/Getty Images

Royal experts and commentators have said the household’s intentions were candid, noble and well-meaning but that the resulting gray space has left people concerned.

“It is uncharted waters. We don’t know what cancer he has or what treatment he is having, but also how long he’s going to be out of action for,” said CNN royal historian Kate Williams.

In the 48 hours since, there has been an outpouring of good wishes both at home and abroad. US President Joe Biden led messages of support from world leaders. He said on social media that the King was in his thoughts.

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People are seen outside Buckingham Palace on February 6.

“Navigating a cancer diagnosis, treatment, and survivorship takes hope and absolute courage,” the president wrote. “Jill and I join the people of the United Kingdom in praying that His Majesty experiences a swift and full recovery.”

Many of the UK’s cancer care charities have also shared encouraging words, including Macmillan Cancer Support, which added that it hoped the King’s openness would encourage the public to get checked. Charles has been the patron of the organization since 1997.

According to Cancer Research UK, around 375,000 new cancer cases are diagnosed in the UK each year. Macmillan Cancer Support estimated in 2022 that there were around 3 million people living with cancer in the UK, predicting that this would rise to 3.5 million by 2025.

Health experts suggest it is not uncommon for cancer patients to be diagnosed when seeking imaging or medical care for other reasons.

“You’re going in for one thing, but then you do additional testing — either as part of a general evaluation or influenced by certain symptoms or signs or blood tests that trigger a procedure or imaging — which then leads to the diagnosis of cancer in a different organ system,” said Dr. Anil Rustgi, director of the Herbert Irving Comprehensive Cancer Center at NewYork-Presbyterian/Columbia University Irving Medical Center, who was not involved in Charles’ medical care.

“A lot depends on what type of cancer and what stage it’s at, but sometimes with early-stage cancer, there are no symptoms,” Rustgi said. “And it’s either detected at the time of screening or incidentally.”

While the palace may not have wanted a frenzy to erupt around the King’s diagnosis, the absence of specifics meant it was somewhat inevitable. Royal biographer Sally Bedell Smith said it is “always tricky to release a partial picture” because people can interpret or over-interpret.

She said times were “very different,” referring to the health battles fought by the King’s grandfather.

“Harking back to his grandfather, George VI, who had arteriosclerosis which was not fully explained to the public and then of course he had lung cancer, and his left lung was removed. The doctors never said it was cancer. They said they had to do it to repair some structural defects,” she said. “They didn’t tell the family; they certainly didn’t tell the public.”

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King George VI is pictured with his grandson, then Prince Charles, on his third birthday in 1951.

With unanswered questions about what Charles is facing, the public are trying to fill in the gaps. Seeing Prince Harry appear to drop everything and fly to London to visit his father, knowing that relations between the pair have been strained over the past several years, has suggested a sense of urgency to some.

But royal experts said there are positive signals that shouldn’t be overlooked. Emily Nash, royal editor at Hello! magazine, told CNN: “If the palace makes the move to appoint the counsellors of state, people might feel their concern rising for His Majesty. These are members of the family who can deputize for him in constitutional affairs if he’s incapacitated or if he’s overseas on other duties. It’s been made very clear to us so far that there’s no plan to bring any of these people into play.”

Two counselors can be appointed to act on the monarch’s behalf through what’s known as a letters patent and help keep the state ticking over. The list of royals who can step in includes Queen Camilla, Princes William, Harry, Andrew and Edward, as well as Princesses Anne and Beatrice. However, it is unlikely Andrew or Harry would be called on as they are no longer working royals.

Nash said it was “very reassuring” that the palace wasn’t looking to install any counselors at this point.

“It really speaks volumes about the King’s determination to continue carrying out his role as best as he can at the moment,” she said. “That means the privy council meetings, the audiences with the prime minister, his red boxes, signing his assent on legislature - these are all key parts of his role that are not public facing so he can continue to do these behind the scenes.”

02:04 - Source: CNN
Why a doctor says Buckingham Palace should release more details about King Charles' diagnosis

The developments of the past few days have reignited a debate over how much the public deserves to know the health of its head of state.

Many feel the family should be more transparent and that the public is entitled to more information as the royal household is taxpayer-funded. Some assert that the public has a right to know because the royals are public figures and personal freedoms are inevitably compromised when representing crown and country. Others argue that by not disclosing the exact cancer, they are inadvertently fueling the gossip.

The public is also aware that the Princess of Wales, who recently underwent abdominal surgery, is still recovering at home in Windsor. She’s not expected to return to engagements until at least Easter. While the public knows her operation was successful, it hasn’t been revealed exactly what it was for. Kensington Palace has been fiercely protective of her, with aides aware of how popular she is while wanting to offer the 42-year-old some privacy.

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Catherine, Princess Of Wales, is pictured at the opening of a new children's day surgery unit in London on December 5, 2023.

“This is what the royals have been wrestling with throughout the 20th century, ever since they let cameras into the coronation of the Queen - how much information to give,” Williams said. “I think, eventually, the King will tell us what cancer it is he has been suffering.”

Historically, specific medical conditions were rarely disclosed to the public. Palace aides would say the family members are entitled to a degree of medical privacy despite their positions as public servants. However, the situation changes when their condition affects their ability to perform public duties. At that point, the palace has a duty to reveal what is going on, which is why a statement was issued on Monday evening.

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Kristina Kyriacou, a former communications secretary to the King, touched on the palace’s approach during an appearance on ITV’s “Good Morning Britain” show on Tuesday. “I have to say, I wouldn’t open the door more. They’ve said a form of cancer has been found, and I personally wouldn’t have advised you go further and say what type of cancer. I think there’s plenty of time for that.

“The trouble is, the more information you give, the more people speculate. The second they know what kind of cancer it is, everyone starts looking it up, people start Googling,” she continued.

Kyriacou said she’d interpreted the palace statement positively and to mean that the condition is treatable.

“I hope I’m right. We should remember at this point, the monarchy are trying not to become the story; I know that’s being a bit laughable for certain members of the royal family in the past couple of years. But Queen Elizabeth and King Charles, they do not want to become the story, they still want to serve their public. In the fullness of time, I would like to think King Charles will talk about his treatment.”

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Britain's King Charles III poses for a portrait in Buckingham Palace's Throne Room after his official coronation in May 2023.
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Charles was born at Buckingham Palace on November 14, 1948. His mother was Princess Elizabeth at the time.
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Princess Elizabeth and her husband, Prince Philip, sit on a lawn with their children Prince Charles and Princess Anne in August 1951.
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Charles attends his mother's coronation in 1953 with his grandmother, left, and his aunt Margaret.
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Charles, right, shakes hands with Sir Gerald Creasy, the governor of Malta, as he and the rest of the royal family visit Malta in May 1954.
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Charles rides with his mother and grandmother as they travel to Westminster Abbey for the wedding of Princess Margaret in May 1960.
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Charles prepares for takeoff during a flying lesson in 1968. In 1971, he earned his wings as a jet pilot and joined the Royal Navy.
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Queen Elizabeth II presents Charles to the people of Wales after his investiture as the Prince of Wales in July 1969.
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Charles walks at Trinity College, Cambridge, where he earned a bachelor's degree in 1970. He was the first royal heir to earn a university degree.
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Charles, left, rides go-carts with his brother Prince Edward and his sister, Princess Anne, circa 1969.
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Charles meets US President Richard Nixon during a private visit to Washington in July 1970.
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Charles attends a conference with his father in November 1970.
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Charles goes on a safari in Kenya in February 1971.
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Charles prepares to fire a bazooka while visiting military barracks in West Berlin in October 1972.
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Charles fishes with a wooden spear circa 1975.
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Charles poses for sculptor David McFall in December 1975.
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Charles smokes a peace pipe during a visit to Canada in July 1977.
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Charles rides a horse during an equestrian event in Cirencester, England, in April 1978.
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Charles, as colonel-in-chief, visits the Cheshire Regiment in Canterbury, England, in November 1978. He served in the Royal Navy from 1971 to 1976, and in 2012 his mother appointed him honorary five-star ranks in the navy, army and air force.
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Charles and Camilla Parker Bowles are seen together circa 1979. They dated in the 70s and would eventually marry in 2005. It was the second marriage for both. Their first marriages ended in divorce.
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Charles poses outside the Taj Mahal in India in 1980.
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Charles kisses his first wife, Lady Diana Spencer, on the balcony of Buckingham Palace in July 1981. Their wedding ceremony was televised.
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Charles and Princess Diana leave a London hospital with their first child, William, in July 1982.
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Charles and Diana dance together at a formal event.
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Charles shares a playful pie in the face while visiting a community center in Manchester, England, in December 1983.
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Charles walks with people in traditional dress on a visit to Papua New Guinea in 1984.
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Charles and Diana sit together in Toronto during a royal tour in October 1991. A year later, they were separated. Charles' affair with Camilla Parker Bowles became public in 1993.
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Charles, Diana and their two sons, William and Harry, gather for V-J Day commemorations in London in August 1995. The couple divorced one year later.
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Charles visits a mosque in London in March 1996.
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South African President Nelson Mandela talks with Prince Charles in London in July 1996.
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Charles poses with the Spice Girls in 1997.
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Charles and his sons spend time together at the Balmoral Castle estate in Balmoral, Scotland, in August 1997.
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Charles, second from right, and Princess Diana's two sisters meet in Paris after Diana was killed in a car crash there in August 1997. She was 36 years old.
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Charles and his sons follow Diana's hearse in London in September 1997.
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Charles stands beside his grandmother's coffin while it lies in state at Westminster Hall in London in April 2002.
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Charles carries a specially painted football through the streets of Ashbourne, England, in March 2003.
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Charles watches a parachute regiment during a D-Day re-enactment in Ranville, France, in June 2004.
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Charles married Camilla Parker Bowles in April 2005.
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Charles, the Prince of Wales, poses for an official portrait in November 2008. He became King after the death of his mother, Queen Elizabeth II.
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Queen Elizabeth II presents Charles with the Royal Horticultural Society's Victoria Medal of Honor during a visit to the Chelsea Flower Show in London in May 2009.
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Charles and Camilla were on their way to a performance at the London Palladium when their car was attacked by angry student protesters in December 2010. The students were protesting a hike in tuition fees.
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Charles and Queen Elizabeth II were among those on the Buckingham Palace balcony after Prince William wed Kate Middleton in April 2011.
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Charles reads the weather while touring BBC Scotland's headquarters in May 2012.
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Charles meets with US President Barack Obama in the White House Oval Office in March 2015.
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Charles and Camilla react as Zephyr, the bald-eagle mascot of the Army Air Corps, flaps his wings at the Sandringham Flower Show in July 2015.
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Members of the royal family pose for a photo at Buckingham Palace in December 2016. From left are Camilla, Duchess of Cornwall; Prince Charles; Queen Elizabeth II; Prince Philip; Prince William; and Catherine, Duchess of Cambridge.
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Charles visits the Italian town of Amatrice in April 2017, after an earthquake had hit.
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Charles and Camilla ride on a raft while visiting the island of Borneo in November 2017.
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Charles leads three cheers for his mother as the Queen celebrated her 92nd birthday at a London concert in April 2018.
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From left, Prince Charles, Prince Andrew, Duchess Camilla and Queen Elizabeth II watch a Royal Air Force flyover in July 2018.
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Charles accompanies his future daughter-in-law, Meghan Markle, as she is married to Prince Harry in May 2018.
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Charles lays a wreath at the Cenotaph in London to commemorate Remembrance Day in November 2018. It was also the 100th anniversary of the end of World War I.
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Charles poses with family members for an official portrait to mark his 70th birthday. He's holding his grandson Prince George as Camilla sits next to his granddaughter, Princess Charlotte. In the back row, from left, are his grandson Prince Louis; his daughter-in-law Catherine; his son Prince William; his son Prince Harry; and his daughter-in-law Meghan.
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Charles speaks at an event in London in March 2020. Later that month, it was announced that he had tested positive for the novel coronavirus.
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Charles and Camilla attend the funeral of Charles' father, Prince Philip, in April 2021.
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Camilla looks on as Charles reacts to a bad pour of beer he made at a brewery in St. John's, Newfoundland and Labrador, in May 2022. They were on a three-day Canadian tour.
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Charles sits by the Imperial State Crown at the opening of Parliament in May 2022. His mother, the Queen, missed the occasion for the first time since 1963. The 96-year-old monarch had to withdraw due to a recurrence of mobility issues.
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Charles is shown skulls of victims during a visit to the Nyamata Church Genocide Memorial in Nyamata, Rwanda, in June 2022. In 1994, Hutu extremists targeted minority ethnic Tutsis and moderate Hutus in a three-month killing spree that left an estimated 800,000 people dead, though local estimates are higher.
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Prince Louis, the Queen's great-grandson, holds his hands over his ears as jets roar over Buckingham Palace during the Trooping the Colour parade in London on in June 2022. From left are Prince Charles; the Queen; Prince Louis; Catherine, the Duchess of Cambridge; and Princess Charlotte.
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Charles has his first audience with Prime Minister Liz Truss after becoming King in September 2022.
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The King speaks in the Throne Room at St James's Palace during the Accession Council in London in September 2022. He was formally proclaimed as King. Joining him were his son Prince William and his wife Camilla, the Queen Consort.
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Charles delivers his first address as King from Buckingham Palace. "As the Queen herself did with such unswerving devotion, I too now solemnly pledge myself, throughout the remaining time God grants me, to uphold the Constitutional principles at the heart of our nation," he said.
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Charles records his first Christmas speech in December 2022. The speech would be broadcast on Christmas Day throughout the United Kingdom.
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The King meets Ukrainian President Volodymyr Zelensky, who was visiting Buckingham Palace in February 2023. Zelensky made a surprise visit to the UK and gave a speech to the joint houses of Parliament.
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The King greets the band Lords of The Lost during a reception in Hamburg, Germany, in March 2023. The King spent three days in Germany for what was his first overseas state visit as monarch.
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The King sits in Buckingham Palace's Blue Drawing Room in March 2023.
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The King attends the 200th Sovereign's Parade at the Royal Military Academy Sandhurst in April 2023.
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Charles receives the St. Edward's Crown during his coronation ceremony at Westminster Abbey in May 2023.
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Charles and Camilla travel to Buckingham Palace after the coronation ceremony.
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The King and Queen stand on the balcony of Buckingham Palace after the coronation. They are joined here by pages of honor who attended them throughout the day. One of the pages was the King's eldest grandson, Prince George, who can be seen second from left.
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Charles and Camilla are pictured with members of the working royal family in May 2023.
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Charles is presented with the Crown of Scotland during a service of thanksgiving that was held at the St. Giles' Cathedral in Edinburgh, Scotland, in July 2023. Scotland was celebrating the King's recent coronation with a day of festivities.
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The King shares a toast with French President Emmanuel Macron during a state dinner at the Palace of Versailles in Versailles, France, in September 2023. It was the first day of Charles' state visit to France.
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The King waves as he leaves the London Clinic with Queen Camilla in January 2024. The King underwent a corrective procedure for an enlarged prostate, CNN understands. In early February, Buckingham Palace announced that the King has been diagnosed with a form of cancer.

Meanwhile, Estelle Paranque, an expert in royal studies and Associate Professor in Early Modern History for Northeastern University London, suggested the type of cancer the King is facing is somewhat irrelevant.

“I don’t think we need to know what type of cancer he has or at what stage. I think we need to know how the royal duties will be handled and by whom and they need to inform us of a plan if things get wrong for the king but apart from that he has a right to privacy. Being diagnosed with cancer is very life-changing. He should be able to handle it the way he needs to.”

The historian added that the palace’s moves on Monday show that Charles wants a more modern monarchy. “He is compromising by revealing the outcome of his medical appointment but he is not revealing everything to keep his privacy safe and that is a smart move,” she said.

CNN’s Catherine Nicholls, Jacqueline Howard and Claudia Rebaza contributed reporting.