All drugs, including heroin and cocaine, should be regulated by the government, a Conservative MP has told BuzzFeed News.
Crispin Blunt, the former prisons minister, said he would like to see measures in place so all drugs could be taxed and controlled, and has called for a public inquiry into whether the law should be changed.
Speaking after an event on cannabis decriminalisation at the Conservative conference in Birmingham, Blunt said he believed prime minister Theresa May could eventually be persuaded to back him due to pressure from the international community.
He told the event he had previously been dissuaded from asking difficult questions about drugs policy by ministers for fear "it might unpick the government’s entire drugs strategy".
“When I ... asked the [government] to tell me just how much did drugs cost the criminal justice system, remarkably, answer came there none," he said.
Earlier this year, Blunt "outed" himself as a user of poppers in an attempt to persuade parliament against making them illegal.
"I think the appropriate next step would be a royal commission to look at policy in this area," said Blunt. "My view is clearly that I would move to regulate all drugs – alcohol is a drug which is regulated and taxed, as is tobacco, and many make the case that marijuana is significantly less toxic than alcohol.
"It’s clearly toxic in some cases and there have been dreadful cases of schizophrenia which appear to come from cannabis use … but, if you have a regulated supply, you have clean cannabis, as you would with every other supply of illegal drug."
Blunt said he was unaware of any Conservative parliamentary colleagues who supported him on drug decriminalisation, saying there was pressure on MPs who wanted to advance their careers to not speak up about the "politically difficult" issue.
"My ministerial career is 100% behind me, so I can be slightly braver about taking positions which I did argue for while in office, but was constrained by collective responsibility," he said.
The former prisons minister said that as more countries and regions decriminalise drugs, it will become more acceptable for ministers, and possibly even the prime minister, to back it in the UK.
"There is a growing body of opinion in support of a royal commission," said Blunt. "It’s not an issue which will go away, because the global environment is changing around us.
"Any number of ministers and presidents are calling for change, and that cacophony will become a crescendo, which may encourage the current ministers to be a bit braver."