Decriminalising cannabis is a “misguided” initiative and risks people’s long-term health, a UN drugs watchdog has warned.
The International Narcotics Control Board (INCB) – a body monitoring drug treaties – criticised moves to weaken drug laws around the world in its annual report.
The group also highlighted the importance of “universal implementation” of international drugs conventions.
Raymond Yans, the President of the INCB, said: “Drug traffickers will choose the path of least resistance, so it is essential that global efforts to tackle the drug problem are unified.”
The INCB’s annual report warned that Colorado’s policy change to allow the commercial sale of cannabis for medical reasons had led to more car accidents involving “drug drivers”.
It also noted an increase in adolescent cannabis-related hospital admissions.
Mr Yans said: “When governments consider their future policies on this, the primary consideration should be the long-term health and welfare of the population.”
Colorado recently relaxed its laws further to allow licensed suppliers to sell cannabis for recreational use to people over the age of 21.
Mr Yans said the INCB “deeply regret the developments” both in Colorado and in Washington, where a similar law has been passed.
The board heavily criticised Uruguay for recently legalising cannabis, warning that the country is contravening international treaties.
The report also highlights the increase in legal highs across the world, including 73 new substances identified in the EU in 2012, compared with 49 in the previous year.
The Home Office is currently undertaking an international review of drugs laws, led by minister Norman Baker who has said legalising cannabis should be considered as an option.