A string of Government ministers yesterday followed Home Secretary Jacqui Smith in admitting they used cannabis in their youth.

A total of seven Cabinet ministers, including Chancellor of the Exchequer Alistair Darling, confirmed they used the illegal drug as students. And two more ministers at the Home Office also said they tried it at university.

The admissions came after Prime Minister Gordon Brown's announcement on Wednesday of a review of the classification of cannabis, which may reverse the 2004 decision to downgrade it from a Class B drug to the less serious Class C.

Mr Brown's spokesman said the Prime Minister - who has denied ever using illicit substances - was "quite relaxed" about his Cabinet colleagues' admissions of past indiscretions.

Ms Smith, who will have to decide whether to reverse her predecessor David Blunkett's decision on cannabis, made her admission on GMTV.

Asked if she had ever tried cannabis, she said: "I have. I did when I was at university. I haven't done for at least 25 years."

Ms Smith said she had "learnt her lesson" from youthful cannabis use and had never tried any other drug.

She told GMTV: "I think it was wrong that I smoked it when I did. I share other people's concerns about the effect that cannabis has on young people and mental health problems."

Asked how she felt about people who thought her admission might make her unfit to be Home Secretary, she said: "On the whole, I think people think human beings should do jobs like this. I am not proud about it, I did the wrong thing.

"I hope that my experiences in my life have actually helped me understand that I do want crime tackled."

Shortly afterwards policing, security and community safety Minister Tony McNulty told BBC News 24: "At university I encountered it, I smoked it once or twice, and I don't think many people who were at university at the time didn't at least encounter it."

And the Home Office later confirmed another minister, Vernon Coaker, who has responsibility for drugs policy, had also taken cannabis in the past.

Mr Darling said he had tried the drug "occasionally in my youth". His deputy at the Treasury, Chief Secretary Andy Burnham said he had used it "once or twice at university and never since".

Spokesmen for Transport Secretary Ruth Kelly and Business Secretary John Hutton also confirmed they were former cannabis users.

A spokeswoman for Ms Kelly said she smoked it "in her youth but realised it was foolish and gave up".

Mr Hutton's spokesman said: "He smoked cannabis when he was at university over 30 years ago. He regrets doing it now, having seen the damage that cannabis can cause among some of the young people in his constituency."

Communities Secretary Hazel Blears and housing minister Yvette Cooper previously admitted taking cannabis in the past.

The Conservative Party said it had nothing new to say yesterday about whether any of the shadow cabinet had used illicit substances.

Tory leader David Cameron has refused to confirm or deny whether he has taken drugs, though a recent biography said he was disciplined in connection with cannabis while a schoolboy at Eton.