George Michael sparks anger after smoking cannabis on TV show

From "Zip Me Up Before You Go-Go" to "Careless Rizla", George Michael's private life has attracted plenty of damaging headlines over the years.

And yesterday the singer was in the firing line again after he was filmed smoking cannabis and talking about his drug use during a television interview.

Michael, who was recently cautioned by police for possession of the drug, was criticised by mental health charities for praising its effects.

In an interview for The South Bank Show filmed in Madrid he tells Melvyn Bragg, the presenter: "This is the only drug I've ever thought worth taking ... this stuff keeps me sane and happy."

His comments drew instant fire from mental health campaigners. Richard Colwill, a spokesman for Sane, said Michael was setting a poor example to his fans around the world.

"There is a growing body of evidence that when cannabis is smoked by young people it can lead to psychosis when their brain is developing," he said.

Paul Corry, director of public affairs at mental health charity Rethink went further, describing the performer's actions and comments as "stupid and naïve", and adding: "As a huge international star, any public comments will draw enormous attention."

William Butler, spokesman for drug and alcohol treatment charity Addaction, said: "We need stronger and clearer messages about cannabis harm so people are in a position to make informed choices. All drugs have potential to harm and that is the principal message we need to get across."

During the course of the interview, recorded backstage after a Spanish concert, the 43-year-old singer admitted the drug could have negative effects and that he regretted taking other stimulants. "It [cannabis] can be a terrible, terrible drug. You've got to be in the right position in life to take it. You've got to have achieved most of your ambitions because it chills you out to such a degree you could lose your ambitions."

But despite his openness, the programme's producers are at pains to point out at the beginning that he has never tested positive for drink or drugs when driving - a reference to a string of recent incidents that have raised speculation over the state of his private life.

But he reassured fans that his mental condition was fine. "The public think I'm a man on the brink of a breakdown because I fell asleep in my car, I hit a parked car and because I cruise as a gay man."

As he prepares to embark on his first world tour for 15 years, expected to include an on-stage Christmas reunion with his former Wham! partner, Andrew Ridgeley, Michael said cannabis helped with the creative process. "I couldn't write without it," he admits.

A spokeswoman for the singer refused to comment but a spokeswoman for The South Bank Show said: "The interview was conducted in Madrid and at his home in England. We must make it clear that when he was smoking he was in Madrid where cannabis use is legal." The interview will be shown on 31 October.