Jack Cunningham, the Cabinet Office minister, will announce - in a Commons statement on Tuesday - tough new targets for cutting crimes committed by drug users as part of a drive to tackle the wide-ranging social effects of narcotics. He will say that the Government aims to reduce addicts' reoffending by a quarter by 2005 and by a half by 2008.
Judges will be encouraged to send offenders for treatment rather than to jail, as ministers believe that many soft-drug users move onto harder substances while in prison.
Tony Blair will say that the policy - which has been piloted around the country - is designed to "break the terrible cycle of drugs and crime which blights so many lives".
New research shows that about a third of 14-year-olds have experimented with illegal substances and the majority of 16-year-olds say they have been offered drugs.
Home Office findings, to be published this week, show a clear correlation between drug abuse and crime. The research, conducted by Keith Hellawell, the Government's drugs "czar", shows that drug addicts are responsible for 30 per cent of all crimes, but only 20 per cent had received any treatment for addiction. It found that heroin and cocaine addicts generally earn between pounds 10,000 and pounds 20,000 a year from crime.
Ministers believe that drug treatment orders - through which addicts are sent for counselling rather than to jail - have been successful in trials and have decided to roll out the programme nationally from April.
George Howarth, the Home Office minister, said yesterday that the Government wanted to take a flexible approach to the problem. "The courts [have] an option to say to young people or anyone involved in drugs and crime, get off drugs and we can work with you," he told the BBC. "The other option might be prison."