King Charles III is suffering from a “form of cancer”, discovered during his prostate operation around ten days ago. The type of cancer was not revealed, but according to a statement from Buckingham Palace, the king began “  regular treatments” on Monday.

No further details are shared about the stage of the cancer or a prognosis, according to the BBC. Other members of the royal family are expected to fill in for him during his treatment, Buckingham Palace said in a press release.