Catherine, Princess of Wales, has said she is "enormously touched" by the support she has received from around the world following her shock announcement that she is being treated for cancer. 

Catherine, 42, revealed Friday that she was undergoing preventative chemotherapy in a video message to the UK, triggering a wave of support from global leaders, family members and the public.

"The prince and princess are both enormously touched by the kind messages from people here in the UK, across the Commonwealth and around the world in response to Her Royal Highness' message," Catherine and her husband Prince William, the heir to the throne, said in a statement released late Saturday.

"They are extremely moved by the public's warmth and support and are grateful for the understanding of their request for privacy at this time."

The announcement ended weeks of speculation about Catherine's health, with many praising her courage and others criticising the conspiracies that spread over her absence.  

The candid disclosure leaves the British monarchy in crisis with King Charles III just weeks ago revealing he was also battling cancer. 

Charles — who was just 17 months into his reign when Buckingham Palace announced in February he would be cancelling all public engagements — led tributes to his "beloved daughter-in-law".

The 75-year-old monarch spoke of his pride in "her courage in speaking as she did".

Global support

Following other warm words from Prime Minister Rishi Sunak and the White House, British newspapers hailed her courage.

"Kate, you are not alone" read the front page of The Sun. The tabloid said it was "hugely comforting" to hear Kate say she was getting stronger.

"Perhaps the world will now appreciate why so much secrecy surrounded her surgery in January," it added.

The Daily Mail tabloid denounced the "social media trolls who have been peddling disgusting conspiracy theories to explain her absence from public life".

Finance minister Jeremy Hunt, whose younger brother died of cancer last year, told Sky News on Sunday that "the thing that really cut me to the quick was when she explained the hardest thing of all for people who've had cancer in their family, which is how you tell your kids".

Outside Kensington Palace in London, Nathaniel Taylor, a 24-year-old government worker, said: "I think it's really damning what happened to them, what the media has done, how they've reacted over these past couple of months.

"I think some speculation is inevitable but the lengths people were going to try and make things up, it's just... Hopefully people take a look in the mirror."

Royal health woes

In her statement, Kate, as the princess is widely known, said the diagnosis was a "huge shock" and asked for "time, space and privacy" as she completes chemotherapy. 

In the video -- recorded on Wednesday in Windsor, west of London, where the future queen and king live with their three young children — she insisted she was "well".

She said it had taken them time to explain the situation to Prince George, aged 10, Princess Charlotte, eight, and five-year-old Prince Louis, "and to reassure them that I am going to be OK".

Buckingham Palace had announced on February 5 that tests had identified Charles had "a form of cancer", without giving further details.  

He has cancelled all public engagements except audiences with the prime minister and ambassadors, and is working on official papers while receiving treatment.  

He has been photographed several times since then, and seen attending church. 

"There's no doubt at all that it's a very, very difficult time for the institution of monarchy," royal expert Richard Fitzwilliams told AFP.

Kate was last seen at a public engagement on 25 December.

Kensington Palace announced on January 17 that she faced up to two weeks in hospital and several months' recuperation following abdominal surgery. 

She was not expected to be ready to return to public duties until after Easter on 31 March, a statement at the time said.

But Kate disclosed that tests after the operation "found cancer had been present" and that she was now undergoing "preventative chemotherapy".

Kensington Palace said she would return to official duties "when she is cleared to do so by her medical team".