Charles was pictured smiling just days after he was admitted to hospital for side effects from his ongoing cancer treatment ...

Although the monarch, 76, is now back home, it is believed he was at The London Clinic, a hospital which treated Charles and Princess Kate last year when they both required surgical procedures.

The London Clinic, an exclusive private hospital nestled in the heart of Marylebone, London, has recently been treating both King Charles III and the Princess of Wales after their cancer diagnoses.