The great class A drugs sale – how prices have tumbled under Labour

'Startling and shocking' figures alarm experts who say cities are awash with heroin and cocaine

Street prices for class A drugs have halved since Labour came to power, dropping almost every year since 1997, government figures confirm. Newly released statistics show that heroin cost as little as £40 a gram in 2007, just over half the price it was 10 years ago. Cocaine was £45 a gram, down from £71.

The shadow home affairs minister, James Brokenshire, says the figures, released in the same week as a UN warning that governments need to do more to tackle international drug gangs, show "10 years of failure" of government drug policies. "The figures are startling and shocking and show the reality of drug use in Britain. It's an indictment of government strategy over the last decade. Sadly, there is not much prospect of improvement," he said.

Experts also describe the figures as "shocking". Professor Neil McKeganey, director of the Centre for Drug Misuse Research at the University of Glasgow, said the figures "show a very gloomy picture". "What worries me is [prices] could drop further as the cost of production and distribution is a small part of the cost," he said.

Kathy Gyngell, research fellow at the Centre for Policy Studies, said: "Addicts reported that in the Nineties £20 would get you 0.2 of a gram of a class A drug. Now it will get you half a gram."

Harry Shapiro of DrugScope, an independent centre of expertise on drugs, said: "These figures confirm the information we have been publishing from our annual street survey of drug prices. We know that there is a lot of heroin about and the consumption of cocaine is going up."

The figures, the first set of official drug-price statistics over a 10-year period, were released in a parliamentary answer to Humfrey Malins MP. "They confirm what those of us on the ground have known for a long while, that the streets of our cities are awash with heroin and cocaine," said Mr Malins, MP for Woking, who is also a leading Conservative thinker on drugs policy, as well as a judge.

"I see the people who are using these drugs come up in front of the courts, and the situation is not getting better," he said.

The Government has just released its much-heralded UK drugs strategy for the next 10 years, announcing that assets will be seized from drugs dealers on arrest, and that addicts who do not undertake rehabilitation will lose their incapacity benefit. Mr Brokenshire dismissed these measures as "gimmicks", saying: "Some of these supposed new policies already exist."

The Home Office urged caution in the reading of the figures, saying they are not definitive, do not reflect regional variations and take no account of drug purity. "Reductions in price may be associated with increased competition or reduced demand, not just increased availability," a spokesman said. "The relationship between drug prices and drug use is not straightforward."

The figures also raise serious issues about the effectiveness of border controls. Law enforcement sources say that the Serious Organised Crime Agency (Soca) and HM Revenue & Customs seizures of class A drugs entering the UK will be down for the fifth year running.

"Price is obviously dependent on demand and supply. There seems to be a big increase in supply for the price to keep dropping," Mr Brokenshire said. "We have been arguing for better policing of our borders."

Professor McKeganey said: "The figures indicate we need to ratchet up the interdiction of drugs coming into the country. It also raises questions about our policy towards Afghanistan and Colombia. We know where the vast majority of these drugs are coming from and yet seem unable to do anything about it."

Ms Gyngell added: "What has happened in the last 10 years or so, despite Home Office claims about... drug use declining or stabilising, is that the number of hard-drugs addicts has tripled while the street price of class A drugs has plummeted, confirmed by these government figures. The failure to control supply of drugs totally undermines treatment investment, which is running to half a billion a year."

The Home Office was adamant that the policy was effective. "In terms of whether enforcement works, our view is that it does and that it plays a vital role in tackling drugs alongside education, early prevention and treatment."