Nick Clegg has accused Theresa May of tampering with a drugs report after it failed to reach satisfactory conclusions.
The Liberal Democrat MP told the Guardian, the Home Secretary “didn’t like the conclusions” of a report released in 2014, which found no clear link between harsh drugs laws and illegal drug use.
The report, Drugs: International Comparators, said its fact-finding did not “observe any obvious relationship between the toughness of a country’s enforcement against drug possession, and levels of drug use”, sparking requests for further talks regarding decriminalisation.
The conclusions were derived from Portuguese data, where the report found there had been “considerable” health improvements since the country began to treat drug possession as a health rather than a criminal issue.
The former deputy prime minister claimed the original draft had been subject to an “endless wrangle between Lib Dem ministers and Theresa May about the fullness of what would be published.”
Mr Clegg, who sits on the Global Commission on Drugs Policy, was one of a number prominent figures who signed an open letter to the UN Secretary General, Ban Ki-moon, urging the UN to review its 20-year campaign to rid the world of illegal drugs, ahead of a special summit in New York next week.
The collective message was orchestrated by the Drug Policy Alliance, which has directed efforts to challenge western policies of criminalising the possession, use and distribution of drugs.
Mr Clegg said the Conservative Government were oblivious to concerns that the war on drugs had failed and accused senior Conservatives of trivialising drug use.
He told the Guardian, Conservative MPs think drug use "is all a slightly naughty recreational secret”.
“They don’t think of whole countries, like Colombia that has been brought to its knees."
In 1998, the UN formally committed itself to abolishing illegal drugs worldwide within 10 years. Recently, however, a reactionary movement has emerged which holds that the so-called War on Drugs, rather than helping the world, has created vast and powerful criminal networks and endless cycles of violence.
The summit, set to open on 19 April, is likely to be a landmark meeting as it appears it will offer a platform to those who question the current drugs policy for the first time.
The session was brought forward two years at the request of Mexico, Guatemala and Colombia, three countries on the front lines of the narcotics conflict.
Responding to Mr Clegg's claims, a Home Office spokesperson said: “We have seen a reduction in drug misuse amongst adults and young people over the last 10 years and more people are recovering from their dependency now than in 2009/10.
"Decriminalising drugs would not eliminate the crime committed by their illicit trade, nor would it address the harms and destruction associated with drug dependence.
"The International Comparators Study does not say there is no link or impact between tough penalties and drug use. It makes clear that approaches to drugs legislation and enforcement of drugs possession are only one element of a complex set of factors that affect drugs use, including prevention, treatment and wider social and cultural factors.”
