One of the world's leading cannabinoid scientists, who pioneered early research on the effects of cannabis in the 1960s and 1970s, has proposed licensing certain forms of cannabis to reduce the risk of people being introduced to harder narcotics and stronger strains of marijuana, like "skunk".
Professor Roger Pertwee, a Professor of Neuropharmacology at the University of Aberdeen, says making less potent forms of cannabis available on the same basis as alcohol would prevent drug-related crime, and could potentially raise billions in additional tax revenue.
He cautioned, however, that arrangements should be made to prevent vulnerable adults and young people obtaining the drug.
"You'd need to have a minimum age of 21, and I would suggest you might even have to have a licence," said Prof Pertwee, from the University of Aberdeen,
"You have a car licence and a dog licence; why not a cannabis licence?"
Speaking to BBC News, he explained: "I'm talking about harm minimisation.
"There is an awful lot of harm being caused by what we have at the moment, with children going to a drug dealer or they try and grow it themselves and then they get into trouble with the law.
"And by dealing with criminals they may well go on to other drugs as well."
As an alternative, Prof Pertwee proposes licensing "suitable suppliers and retail outlets" and allowing "marketable, branded products" that are "as safe as possible".
He does not advocate licensing products that can be sold in cigarette form, however, such as "joints".
Instead, he said that cannabis licences could be tied to certain delivery mechanisms, such as "volcanoes", which heat rather than burn cannabis to produce a vapour that avoids the carcinogenic effects of cannabis smoke.
The Home Office has dismissed Prof Pertwee's proposals: "There is clear evidence that cannabis is a harmful drug which can cause damage to mental health in the immediate and longer-term.
"Even the occasional use of cannabis can be dangerous for people with diseases of the circulatory system.
"The Government does not believe that decriminalisation of cannabis is the right approach. Our priorities are clear: we want to reduce drug use, crack down on drug-related crime and disorder and help addicts come off drugs for good."