The survey by Brake and Direct Line found that there is a continued lack of understanding amongst drivers and motorcyclists about how long alcohol stays in the body, with 38% admitting to driving the morning after a heavy night. This is more than a 30% increase compared to seven years ago, when 28% admitted to doing so.

The survey also suggests that many drivers are putting themselves and others in danger due to a lack of awareness that even a small amount of alcohol affects driving:

• One in three (35%) admit driving after drinking alcohol (any amount) in the past year – although this has fallen from 51% in 2003

• Nearly half (45%) believe they would need to consume two or more units for their driving to be affected – with a worrying one in seven (14%) believing it takes three or four units or more

Julie Townsend, Brake's campaigns director, said: 'Drink-driving remains a menace on our roads, devastating people's lives every day. A shocking proportion of drivers seem unaware of the dangers of driving the morning after a heavy night, or even small quantities of alcohol. We're appealing to everyone to stay safe over the festive season by planning ahead – make sure you can get home safely, and stay off the booze if you're driving home or early the next day.'

The Government is also being urged to take action on drink-driving following recent recommendations from parliament's Transport Select Committee and an independent review by Sir Peter North earlier this year. The Committee called for drink-drive enforcement and educational campaigns to be stepped up, while Sir Peter North advocated a lowering of the drink-drive limit.

Ms Townsend commented: 'We're calling on the Government to lower our drink-drive limit and enable the police to dramatically step up enforcement. These are crucial steps in stamping out drink driving, and eliminating the needless tragedies it causes.'