King Charles has joked about getting old, telling a fellow cancer patient that "bits don't work so well once you get past 70".
The monarch, who will celebrate his 77th birthday in November, was visiting a new hospital in the West Midlands when he made the comment.
It was the King's first engagement since holidaying at Balmoral Castle in Scotland with the extended royal family .
The King is still undergoing regular treatment for an undisclosed type of cancer, following his diagnosis in February last year.
He had surgery for a benign prostate enlargement and the cancer was detected soon after. But Buckingham Palace has confirmed the King was not diagnosed with prostate cancer.
The monarch has been carrying out a full diary of events since taking a brief break from p