MPs must acknowledge that not all drug use is problematic and should consider decriminalising possession of small amounts of controlled substances, a report by independent experts urged Monday.

The six-year study by the UK Drug Policy Commission (UKDPC), an independent advisory body made up of leading scientists, police officers and academics, concluded that current policies make little impact on drug use, and in some cases make it worse.

The report called for civil penalties such as fines to replace the criminal sanctions imposed on the 42,000 people sentenced each year for possession of all drugs, saying it would not lead to significant increase in use.

Those growing cannabis for personal use should also only face minimal sanction, according to the panel.

But the report maintained that harder drugs such as heroin and cocaine should still remain illegal.

"Taking drugs does not always cause problems, but this is rarely acknowledged by policymakers," the report concluded.

"In fact most users do not experience significant problems, and there is some evidence that drug use can have benefits in some circumstances."