Emmanuel Macron and a “worried” Joe Biden offered well wishes for Britain's King Charles overnight after news of his shocking cancer diagnosis broke.
Buckingham Palace announced the news on Monday evening, saying the monarch had already started treatment following the discovery of the cancer.
His diagnosis means that, less than 18 months into his reign, the 75-year-old will suspend public engagements but continue to run state affairs and not relinquish his constitutional roles as head of state.
World leaders, many of whom Charles met during his decades of royal service, expressed hope that the British king makes a speedy recovery.
US President Joe Biden said he was “concerned” about the king's cancer diagnosis as foreign leaders wished him a speedy recovery, while President Macron – who is said to have a warm relationship with Charles – expressed France's friendship.
Emmanuel Macron and a “worried” Joe Biden offered well wishes for Britain's King Charles overnight after news of his shocking cancer diagnosis broke. Macron (seen with Charles in Paris last year) is believed to have a warm relationship with the British monarch
Mr Biden, who is six years older than the 75-year-old king, was asked by reporters if he had a message for Charles during a visit to Las Vegas.
The President replied, “I'm worried about him.” Just heard about his diagnosis.
“I’ll talk to him, God willing.”
Mr. Biden later tweeted: “Dealing with a cancer diagnosis, treatment and survival requires hope and absolute courage.”
“Jill and I join the people of the United Kingdom in praying that His Majesty makes a speedy and full recovery.”
His predecessor in the White House, Donald Trump, described the king as a “wonderful man” who he met during his time as US president.
The Republican Party's leading candidate in the upcoming presidential election posted on his Truth Social platform: “King Charles has cancer.”
“He is a wonderful man who I have gotten to know well during my presidency, and we all pray for his speedy and full recovery!”
Canadian Prime Minister Justin Trudeau also sent his best wishes.
He tweeted: “I, like Canadians across the country and people around the world, are thinking of His Majesty King Charles III as he undergoes cancer treatment.”
“We send him our best wishes – and hope for a speedy and full recovery.”
Canada is one of the 14 Commonwealth realms where the king is the head of state.
The leader of Commonwealth member Australia said his country's thoughts were with the king and his family.
Prime Minister Anthony Albanese said: “Australians know that His Majesty King Charles has always turned to us in our country's most difficult moments, extending kindness and care to those who are struggling.”
US President Joe Biden (seen shaking hands with Charles in July last year), who is six years older than the 75-year-old king, was asked by reporters if he had a message for Charles during a visit to Las Vegas
Joe Biden's predecessor in the White House, Donald Trump, described the king (pictured together in 2019) as a “wonderful man” who he had met during his time as US president
“We are all thinking of him and his family at this very difficult time.”
“We wish him all the best and a speedy recovery.”
Mr Albanese, who has said he believes an Australian citizen should replace the British monarch as the country's head of state, recently shelved a plan to hold a referendum on the creation of a republic.
French President Emmanuel Macron tweeted: “I wish His Majesty King Charles III. a speedy recovery.” Our thoughts are with the British people. Amities (friendship).'
King Charles and Macron are said to have a “warm relationship” which grew after the French president gave the king a gift following the queen's death.
The British monarch can also speak French, having learned it at school, and has often visited France in his capacity as a senior royal.
Irish President Michael D. Higgins “regrets and is very concerned about today's statement regarding King Charles' medical diagnosis,” a statement on his behalf said.
“The President, on behalf of the Irish people, extended his best wishes to King Charles for his medical treatment and for his full recovery, and to Queen Camilla and his family.”
Israeli Foreign Minister Israel Katz sent “prayers and wishes for the full and speedy recovery of the friend of the Jewish people, King Charles.”
Charles, who became king following the death of his 96-year-old mother, Queen Elizabeth II, on September 8, 2022, is generally in good health, apart from injuries from polo and skiing.
But the palace said that during his recent hospital procedure for benign prostate enlargement, “another issue was noted.”
“Subsequent diagnostic tests identified a type of cancer,” the palace said in a statement, adding that he had begun treatment, but without elaborating on the type of cancer found or how advanced it was.
The palace said the king was “completely optimistic” and looked forward to returning to full public service as soon as possible.
Irish President Michael D. Higgins (seen shaking hands in Northern Ireland in September 2022) “is very saddened and concerned by today's statement regarding King Charles' medical diagnosis,” a statement on his behalf said
French President Emmanuel Macron tweeted: “I wish His Majesty King Charles III. a speedy recovery.” Our thoughts are with the British people. Amities'
Doctors have advised him to postpone public duties, but he will continue to “carry out state business and official formalities as usual,” the palace added.
Last month, Charles received widespread praise for speaking openly about his benign prostate condition. Doctors said this raised awareness and resulted in many more people coming forward with symptoms.
He was discharged from a London hospital a week ago after a three-day stay for corrective surgery.
The palace added that the king decided to share his cancer diagnosis “to prevent speculation and in the hope that it may contribute to the public's understanding of all people affected by cancer around the world.”
Charles deviated from royal tradition by being open about his prostate disease. For centuries, the British royal family remained secretive about health issues.
When Britain's monarchs were truly in power, news of disease was withheld for fear it would weaken their authority.
The habit of secrecy persisted after royals became constitutional figureheads.
The British public was not told that Charles' grandfather, King George VI, suffered from lung cancer before his death in February 1952 at the age of 56, and some historians have claimed that the king himself was not told that he was terminally ill be.
In the final years of Elizabeth's life, the public was only told that the Queen suffered from “mobility problems.”
The death certificate only stated “age” as the cause of death.
Pat Price, founder of the Catch Up With Cancer campaign, said millions shared the “collective concern” for the royal's health but praised him for his candor.
“The King's openness about his battle with cancer is a stark reminder that one in two of us could develop cancer at some point in our lives,” Price said.
The diagnosis will extend the shortage of frontline royals caused by Charles' prostate surgery and the almost simultaneous hospitalization of Catherine, Princess of Wales.
Catherine, 42, the wife of Charles' son and heir to the throne Prince William, underwent abdominal surgery at the same hospital where Charles was treated.
She left last Monday on the same day as Charles after a stay of about two weeks and may not return to public duties until late March.
The Royal Standard flies over Buckingham Palace following the announcement that Britain's King Charles has been diagnosed with cancer on February 6 in London, Britain
Pictured is a car believed to have Prine Harry on board arriving at LAX airport on Monday
Her husband William, 41, also temporarily withdrew from scheduled engagements to help look after their three children, although he is expected to return to his royal duties this week.
At the time of Catherine's surgery, Kensington Palace stressed that her condition was not related to cancer, without elaborating.
The couple's absence left Queen Camilla, Charles' 76-year-old second wife, the most visible face of the royal family.
Prince Harry, meanwhile, said he had spoken to his father and would visit him in Britain and was on his way to London on Tuesday morning.