David Cameron last night dismissed calls for a Royal Commission into drugs policy - and insisted the Government would not go soft on banned substances.
A report by MPs published yesterday called on ministers to consider adopting the Portuguese system, under which possession of small amounts of drugs - even Class As such as heroin and cocaine - is not a criminal offence.
Instead users can be handed a spot fine or have their passport taken away, and addicts are encouraged to seek treatment.
But the Prime Minister, speaking on a visit to Cambridge said: ‘I don’t support decriminalisation. We have a policy which actually is working in Britain.
‘Drugs use is coming down, the emphasis on treatment is absolutely right, and we need to continue with that to make sure we can really make a difference. Also, we need to do more to keep drugs out of our prisons.
‘These are the Government’s priorities and I think we should continue with that rather than have some very, very long-term Royal Commission.’
MPs on the Home Affairs Committee travelled to Portugal and said they were ‘impressed’ by its system of giving users civil penalties for up to two grams of cocaine and 25g of cannabis.
They said: ‘It had clearly reduced public concern about drug use in that country, and was supported by all political parties and the police.’
‘Although it is not certain that the Portuguese experience could be replicated in the UK, given societal differences, we believe this is a model that merits significantly closer consideration.’
Mr Cameron’s comments were in stark contrast to his drugs minister, Jeremy Browne, who yesterday said ministers were ‘open minded’ about what to do about drugs.
The Liberal Democrat Home Office minister told the Today programme the Government was ‘open to new ways of thinking’.
He said: ‘We are open-minded, we think it’s a decent, thoughtful, balanced report. We will consider it carefully.
Mr Browne refused to criticise the report, and said a Royal Commission was not the answer ‘at this time’
He said: ‘The Home Secretary has said she doesn’t think the Royal Commission is the answer at this time, but we are open to new ideas and evidence-based research to carry on reducing the harm caused by drugs in this country.”
The report also urged the Government to conduct detailed studies of how the law operates in two U.S. states - Washington and Colorado - where cannabis is being legalised.
It pointed to the lives lost to drugs violence and organised crime in Latin America as a reason why Britain and other countries should change the law.
The report also called for cannabis to be downgraded from Class B to C - lowering the criminal penalties for possession and dealing. And it said cannabis warnings should not appear on criminal record checks.
But anti-drugs campaigners warned legalising would lead to a drugs ‘free-for-all’ and send the message that taking drugs was safe.
Illegal drug use in England and Wales is at its lowest level for more than a decade. But at the same time, many drug users have switched to so-called legal highs which are emerging at a rate of one a week.