Ninety five tonnes of marijuana was produced in the UK in 2016 for medicinal and scientific use, accounting for 44.9 per cent of the world total, its International Narcotics Control Board (INCB) found.
The UK is also the largest exporter of the drug, with 2.1 tonnes exported in 2016 – roughly 70 per cent of the world’s total, the report stated.
Recreational use of cannabis is illegal in the UK, but in recent years, there has been a growing interest in its using it for medicinal purposes.
A number of advocacy groups have called on the government to allow it to be used in treatments.
Drug policy reform group, Transform, criticised the government for being a mass producer while “consistently refusing to allow medical cannabis in the UK on the basis that it has ‘no therapeutic value’”.
Steve Rolles, its senior policy analyst said: “It is scandalous and untenable for the UK government to maintain that cannabis has no medical uses, at the same time as licensing the world’s biggest government-approved medical cannabis production and export market.
“UK patients are either denied access and suffering unnecessarily, or are forced to buy cannabis from the criminal market.
“Countries with proper access to medical cannabis do not have this problem, as standardised cannabis products are in the hands of doctors and pharmacists.”
It comes after a report found the illegal UK cannabis market is dominated by high-potency “skunk” and weaker varieties of the drug have been pushed out.
The study, conducted by King’s College London researchers, found high-potency varieties constituted 94 per cent of police seizures in 2016.
It was the first comprehensive, wide-ranging survey of cannabis strength published in Britain for almost 10 years.