Europeans are abandoning cannabis but turning to cocaine and drink, new figures from French customs reveal.

According to a report by the Central Narcotics Office, after more than a decade of rapid growth, seizures of cannabis resin in Europe dropped by a fifth last year, to 831 tonnes. At the same time, seizures of cocaine grew by 15 per cent.

The apparent trend is reinforced by British figures which show that the popularity of cannabis in the UK has plummeted, with 600,000 fewer people smoking or eating marijuana than three years ago. The Home Office statistics, released last week, also show that consumption of cocaine in Britain has risen.

The figures will help the British government and other European nations with more liberal drug laws such as Holland and Switzerland rebut claims that their approach to cannabis leads to increased use of the drug. The growing cocaine use will, however, worry European anti-narcotics police and many politicians.

'Seizures in Europe have increased over the last several years, confirming the maturing of the cocaine market in western Europe,' said Interpol, the transnational police agency. 'Recent reports, particularly from northern [European] countries, suggest young adults are increasingly using cocaine rather than amphetamine-type stimulants. This change is likely to be the result of the increased availability and lower price of cocaine, as well as government campaigns against amphetamines.'

Despite apparent success by police - Bernard Petit, head of France's anti-Narcotics squad claimed last week that 90 of the 250 tonnes of cocaine imported onto the continent were seized - the price of the drug is lower than it has ever been.

'Drugs gangs know where the profits are and can afford to lose most of their shipments,' said one former senior British customs officer. 'They are focusing more and more on cocaine. No one serious traffics or deals cannabis any more.'

Possible explanations for the decrease in cannabis use include the growing awareness that cannabis can cause mental health problems, and the fact that in the UK and France marijuana abuse is being replaced by binge-drinking.

In France, cannabis use has levelled out while heavy drinking sessions have become more common, with almost half of all teenagers in a study this summer saying that they had had more than five drinks in one evening in the last month.

'This consumption pattern corresponds to the phenomenon of "binge-drinking" seen in Britain and America,' said Jean-Michel Costes, of the National Observatory of Drugs and Addicts.

Frederic Rouillon, a French drug expert, told Le Monde last week that ideas that Americans used stimulants whereas Europeans used sedatives were outdated. 'The fashion for cocaine has eroded that distinction,' he said.