AUSTRALIA and New Zealand have a proud history of co-operation, but now it seems we have achieved a more dubious honour: we are the world's biggest pot-heads.

Together we have higher levels of marijuana and amphetamine use than any region in the world, according to the findings from a series of papers to be published today in the leading medical journal The Lancet examining global drug use and law enforcement.

In 2009 in Oceania, for which data only from Australia and New Zealand was available, 9.3 to 14.8 per cent of people used marijuana in the past year, compared with 1.2 to 2.5 per cent in Asia, which had the lowest use.

Between 2 and 2.8 per cent used amphetamines such as speed, compared with between 0.2 to 1.4 per cent in Asia.

The study leader, Louisa Degenhardt, of the National Drug and Alcohol Research Centre and the University of NSW, said Australia and New Zealand's similarity in drug use patterns pushed Oceania figures so high.