Britain is to become the only European country that allows motorists to have at least one alcoholic drink and still be legally fit to drive.

The Times has learnt that the Government has changed its mind about reducing the limit from 80 to 50 milligrams of alcohol per 100 millilitres of blood, despite evidence that a lower limit would save 65 lives a year.

Road safety groups believe that the existing limit encourages people to take chances and have a drink or two before driving. With a 50mg limit, drivers would be at risk of prosecution after just one drink.

In mainland Europe, the limit is either 50mg or 20mg. The Republic of Ireland still has an 80mg limit but says that it will reduce it to 50mg next year.

The Association of Chief Police Officers, the British Medical Association and the Royal Society for the Prevention of Accidents all support a reduction to 50mg.

In July Sir Liam Donaldson, the Chief Medical Officer, said that the limit for drivers aged 17 to 20 should be cut to zero.

Research by University College London found that lowering the limit for all drivers to 50mg would prevent 65 deaths and 230 injuries a year in Britain. It would also save the economy £119 million a year by reducing medical costs and lost working time.

Last year Stephen Ladyman, then road safety minister, said that the Government was in favour of moving to a 50mg limit and would include the proposal in a public consultation.

But his successor, Jim Fitzpatrick, has told The Times that the consultation document, to be published within weeks, will not propose a lower limit.

He said: “It will not be recommending a reduction from 80 to 50. We are not convinced that dropping to 50 is the right answer. Drivers who are between 50 and 80mg are not the ones we are most worried about. It’s the ones above 100.

“If you look at a comparison with other countries which have 50 rather than 80, our safety levels compare very favourably.”

In the past five years, Britain has lost its place at the top of the European Union’s road safety league. The Netherlands and Sweden now have lower road death rates, and have been more successful in reducing drink-drive crashes. In the Netherlands the limit is 50mg and in Sweden 20mg.

Mr Fitzpatrick said that the consultation would focus instead on better enforcement of the existing limit. Police could gain new powers to stop and test drivers at random rather than, as at present, needing to have suspicion that an offence is being committed.

The courts may also gain new sentencing powers to require repeat or serious offenders to have “alcolocks” fitted to their cars after they have served bans. Alcolocks work by linking the ignition to an on-board breathalyser.

By leaving the alcohol limit unchanged, the Government will avoid the awkward question of whether to introduce a lower penalty for registering just over 50mg. At present, anyone caught drink-driving serves a minimum ban of 12 months. Most countries that have lower limits only fine drivers and give them penalty points for minor breaches.

Andrew Howard, head of road safety at the AA, said that the motoring organisation used to oppose any lowering of the limit but had changed its position recently.

“We surveyed 14,000 of our members and found that 70 per cent were in favour of reducing the limit. So our position now is that we would not oppose a reduction,” he said. “However, we have to ask whether a policeman who finds a driver with an alcohol level of 55mg would be better giving him a thorough telling-off rather than spending two hours taking him to the station. That policeman could be more useful out on the roads looking for someone two or three times the limit who poses a much greater danger.”

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