King Charles III has made his first public comments since being diagnosed with cancer last week.

In a message, written from his estate in Sandringham in Norfolk, he said:

"I would like to express my most heartfelt thanks for the many messages of support and good wishes I have received in recent days.

As all those who have been affected by cancer will know, such kind thoughts are the greatest comfort and encouragement."

The 75-year-old monarch also reflected on his decision to publicly reveal his illness.

"It is equally heartening to hear how sharing my diagnosis has helped promote public understanding and shine a light on the work of all those organisations which support cancer patients and their families across the UK and wider world."

He added he is extremely grateful for the medical professionals who have helped him: "My lifelong admiration for their tireless care and dedication is all the greater as a result of my own personal experience."

Charles started his treatment in London on Monday, and on Tuesday flew to Sandringham with Queen Camilla. Buckingham Palace hasn't disclosed what sort of cancer he has, but it's known not to be prostate cancer.

It's not known whether he will need to return to London for further treatment.

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