The decision, announced by Home Secretary David Blunkett in the House of Commons, stirred criticism from the Conservative opposition and some Labor politicians and prompted the country's former antidrug chief to resign as a government adviser because, he said, Britain is "moving further toward decriminalization than any other country in the world."

Mr. Blunkett tempered his announcement, which takes effect next July and puts cannabis on a par with antidepressants and steroids, by saying he would also raise the punishment for marijuana dealing and step up drug education and treatment for abusers.

An estimated five million people in Britain regularly use marijuana, and government data show that its use has risen sharply in the last 20 years.

A study published last year on drug habits in the European Union showed that 20 to 25 percent of adults in Britain used marijuana — about the same rate as shown for Denmark, France, Ireland, the Netherlands and Spain.

The government action followed recommendations of a parliamentary committee in May, which said a new attitude of tolerance would give drug policy greater credibility among young people and help the police direct resources toward heroin and cocaine. Britain has the most drug-related deaths of any country in the European Union, with heroin cited as the principal cause.

The parliamentary committee also suggested reclassifying the drug Ecstasy, but Mr. Blunkett said he had rejected that advice.

Several other European countries have already relaxed their drug laws. The Netherlands has legalized marijuana, while Luxembourg has ended jail sentences for marijuana possession. Spain and Italy do not jail people caught with drugs meant for personal use. Last year Portugal eliminated jail time for possession of small amounts of any illegal drug.

Under the British reform, possession of marijuana would no longer be considered an arrestable offense. Though that will not take effect for a year, from now on any police action will be limited to issuing a warning and seizing the drug.

Mr. Blunkett countered suggestions that Britain was going "soft on drugs" by saying the police would retain the right to arrest users in cases like smoking outside schools or in the presence of children. The Home Office emphasized that any marijuana cafes where the drug was sold and used openly remained illegal and would be closed.

"It is critical that police can maintain public order," Mr. Blunkett said. "Where cannabis possession is linked to aggravated behavior that threatens public order, the police will retain the power of arrest."

Scotland Yard said it welcomed the reclassification of the drug combined with maintaining a discretionary police power to intervene. The drug spokesman for the Association of Chief Police Officers, Andy Hayman, said, "The retention of police power of arrest will enable the police to have greater flexibility in dealing with incidents on the street."

Mr. Blunkett insisted that today's move did not constitute legalizing marijuana. "All controlled drugs are harmful and will remain illegal," he said. "We must concentrate our efforts on the drugs that cause the most harm, while sending a credible message to young people."

But Keith Hellawell, Prime Minister Tony Blair's onetime antidrug chief, said the new policy "would virtually be decriminalization of cannabis, and this is, quite frankly, giving out the wrong message."

He coupled the announcement of his resignation from a government advisory post with a strong attack on the policy, saying it would damage communities and lead to more, not less, drug use.

"It's actually a technical adjustment which in the reality of the law doesn't make a great deal of difference," Mr. Hellawell said, "but it's being bandied about by people as a softening of the law."

He said that there had been an increase in marijuana smoking among young people and that more people were seeking treatment for its effects. "Why on earth, when there are these problems, we change our message and give a softer message, I don't know," he said.

Mr. Hellawell, the former chief constable of West Yorkshire, was named the government's first antidrug coordinator by Mr. Blair in 1997, but last year he was sidelined by Mr. Blunkett from the $160,000-a-year post and made a part-time adviser on the international drug trade.

The new police tolerance has been in effect on an experimental basis in two London neighborhoods, Lambeth and Brixton. The Conservative leader, Iain Duncan Smith, visited the Brixton project on Tuesday and told the Commons today that residents had told him it had led to rampant dealing on their streets. He said Mr. Blunkett's plan amounted to "handing over drugs policy to criminals on the street."

Oliver Letwin, the Conservatives' spokesman on law enforcement, complained that "the middle ground of calling it illegal, leaving it in the hands of dealers rather than in legitimate tobacconists or whatever, then turning a blind eye to it, is the worst of all worlds."

Kate Hoey, a Labor member of Parliament who represents one of the affected London areas, said the government could live to regret today's decision because of the increasing strength of marijuana being peddled on the street.

"It is a very strong type of cannabis, it's genetically modified, it is not perhaps like people tried 20 years ago," she said, "and we have no idea of the long-term effects of constant hard smoking that some kids are doing now."

Copyright 2002 The New York Times Company

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