David Cameron will receive a letter from over 90 celebrities, politicians, lawyers and health experts, calling for a review of the current policy on the possession of illegal drugs.

Russell BrandRussell Brand has thrown his weight behind the campaign [Photo: Getty Images, credit: Mary Turner]

Public figures such as Russell Brand, Sting, Sir Richard Branson and Will Self as well as signatories from law enforcement, the Prison Governors Association and the National Black Police Association, have all supported the letter for change, which was drafted by the drug charity, Release.

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Nick Glynn, vice-president of the National Black Police Association, said: "It is time for a mature, informed, objective debate around the UK's drugs laws. Enforcement of the 1971 Misuse of Drugs Act has created many unintended, negative consequences and new approaches must be considered, including those which have been successful in other countries. Strategies that avoid criminalising people and focus instead on health and education seem to me to offer a positive way forward."

This isn’t new territory for Cameron; during his time on the home affairs select committee in 2002, it was recommended that the government "initiates a discussion within the Commission on Narcotic Drugs of alternative ways—including the possibility of legalisation and regulation—to tackle the global drugs dilemma".

The letter also highlights research to show that drug laws are unreasonably used against black people in England and Wales, and that they are six times more likely than white people to be stopped and searched.

Will SelfWill Self has also backed the campaign [Photo: Getty Images, credit: Ian Gavan]

In addition to the letter – which says the use of legal sanctions for the possession of drugs in the UK has led to the "unnecessary criminalisation" of more than 1.5 million people in the last 15 years - protests are planned for 100 cities across the world. In the UK, protesters are making their voices heard in Parliament Square. 

"The global day of action is a public show of force for drug policy reform," Ann Fordham - the executive director of the International Drug Policy Consortium, which focuses on issues related to drug production, trafficking and use – said. "The tide is turning and governments need to urgently fix their drug policies and repair the damage that has been done," she said.

Niamh Eastwood, executive director of Release, the organisation leading the action, said: "The drug policy reform debate has moved forward in recent years and the UK government needs to be at the forefront of it. In 2002, when the prime minister was a member of the Home Affairs select committee, he supported the recommendation that the UN consider alternatives to the status quo. We are asking him to stand by that commitment and recognise the damage that has been done, both nationally and internationally, by repressive drug policies."