The government will look into reclassifying cannabis as a class B drug, following concerns about stronger strains of the drug.
Gordon Brown announced today the Advisory Council on the Misuse of Drugs (ACMD) will look again at penalties for possessing and using cannabis.
It was downgraded from a class B to a class C drug in 2004 by the then home secretary David Blunkett.
Since then it has been classed alongside anabolic steroids and possession has been a largely non-arrestable offence.
The prime minister told MPs the government is considering returning it to Class B - putting it on a par with amphetamines - following claims new, stronger versions of the drug are linked to mental health problems.
The Home Office confirmed: "We will be asking the ACMD to review the classification of cannabis, given the increase in strength of some cannabis strains and their potential harms.
"It would be wrong to prejudge that review which shows how seriously we take our priority of reducing drug-related harm."
Cabinet has already been briefed of the review. Jacqui Smith will publish a consultation document next week to seek responses from the public.
Mr Brown said: "She will be asking the public to comment on new ways in which to improve drugs education in the country, give support to people undergoing treatment.and give support for communities who want to chase out drug dealers from their communities".
Frank, the government's drug information website, said that stronger forms of cannabis are now available.
David Cameron has warned of the increased potency of the drug.
Speaking at a young people's charity last week he said: "I think the most persuasive argument here is the change in the strength of cannabis.
Mr Cameron told the audience he had accompanied police on a drug raid: "Before the bag was even open, the smell was unbelievably strong. Grown in greenhouses, this skunk is unbelievably powerful."
"And it is completely different to," he began before saying, "I think I'll stop there."