He said he'd puffed on a few ciggies behind a chicken coop when he was a schoolboy.
The heir to the throne made the revelation to, of all people, a group of respiratory nurses at a Clarence House function.
Nurse and secondary school teacher Paul Watson, 39, from Peterborough, said: "There was a few of us that are respiratory nurses and he asked whether we deal with a lot of smokers.
"He said, "I gave up at 11 when I had a few cigarettes behind a chicken coop.'
"I believe it was tongue in cheek."
One is, cough, cough, not, cough, amused!