The Duchess of Cambridge, as Patron of Action on Addiction, is visiting the charity's Hope House treatment centre in Clapham, south London.
More top news
The singing star had earlier cut short a performance in Auckland after he lost his voice and needed medical help on stage.
The 77-year-old squared up to the assailant during an attempted robbery outside a Sainsbury’s supermarket in Cardiff.
Feeling chilly with blustery downpours moving through