More than 80 per cent of the world’s population has little or no access to pain-relieving drugs, a report revealed.

Hamid Ghodse, the president of the International Narcotics Control Board (INCB), said the situation was “extremely unfair and extremely problematic”.

The INCB annual report revealed that the majority of the world’s legal medical drugs – licit drugs – were used by 10 per cent of the world’s population, typically in rich countries in the West.

The US accounted for 56 per cent of the world’s morphine consumption in 2009 alone.

Mr Ghodse said: “90 per cent of the licit drugs are consumed by 10 per cent of the world’s population, in the United States, Australia, Canada, New Zealand and some European countries.”

The INCB report found there was enough raw material to meet the demand for all patients needing opioid analgaesics – opiate-based pain killers such as codeine and morphine. But numerous barriers preventing access to the drugs were in place, such as lack of education of health professionals, legal constraints, distribution difficulties and an absence of comprehensive health policies.