King Charles III has been diagnosed with cancer, Buckingham Palace has confirmed in a statement early this morning.
The king was diagnosed after his recent hospital treatment for benign prostate enlargement.
He is beginning treatment today, the palace said.
In the meantime, the king will step back from "public facing" duties.
"Throughout this period, His Majesty will continue to undertake State business and official paperwork as usual," the palace said.
"The King is grateful to his medical team for their swift intervention, which was made possible thanks to his recent hospital procedure.
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"He remains wholly positive about his treatment and looks forward to returning to full public duty as soon as possible.
"His Majesty has chosen to share 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."
The palace has not specified what kind of cancer the king has.
It's understood the public announcement of his illness was delayed in order to allow Charles to tell his family privately.
He appeared in public following his regular church service at Sandringham on the weekend, waving to onlookers.
Prime Minister Anthony Albanese said the thoughts of all Australians would be with the royal family today.
"I will be sending a message to the palace this morning," he said.
"And we hope that King Charles has a speedy recovery and a return to his duties as soon as possible."
Albanese's UK equivalent Rishi Sunak posted on X his hopes for the king's "full and speedy recovery".
"I have no doubt he'll be back to full strength in no time and I know the whole country will be wishing him well," he said.
The BBC has reported that the king's younger son, Prince Harry, will travel to the UK to meet with his father.
Harry and his wife, Meghan, have been estranged from the royal family over racism allegations.
The Prince of Wales, William, has also recently stepped back from public duties to care for his wife, Catherine, who recently underwent abdominal surgery.
King Charles, 75, ascended to the throne after the death of his mother Queen Elizabeth II on September 8, 2022, and was crowned in May last year.
