Road safety charity Brake and Direct Line are appealing to party-goers to help prevent Christmas tragedies by standing up to designated drivers who break their promise by drinking alcohol.

Research released today by Brake and Direct Line, shows a huge shift in public attitudes towards drink driving over the past decade.

While the vast majority of drivers now subscribe to a zero tolerance approach to alcohol and driving, in line with Brake's advice, a minority continue to cause enormous risk by driving after drinking - and passengers are struggling to stand up to these drivers.

The survey of 1,000 drivers across the UK found:

• Two-thirds of drivers (68%) won't drive after having a drink, compared to less than half (49%) a decade ago. The remaining one-third (32%) admit driving after drinking some amount of alcohol, or the morning after having a lot to drink, in the past year.

• One in ten (10%) admit driving after drinking so much that they think they were certainly or potentially over the legal limit in the past year.

• Four in five (81%) never drive first thing in the morning after drinking a lot of alcohol, up from 72% a decade ago.

• While more and more drivers are committing to zero tolerance, passengers are struggling to stand up to drink drivers. Only one-third (36%) said they would refuse to get in the car if their designated driver had been drinking. One in eight (12%) say they have potentially or definitely been a passenger with a driver who was over the limit in the past year.

In 2012, 280 people were killed and 1,210 suffered serious injuries in crashes caused by drivers over the drink drive limit. It's estimated a further 65 deaths are caused annually by drivers who have been drinking but are under the limit.

These deaths and injuries cause a huge amount of pain and suffering to those involved and the families left behind, many of whom are supported by Brake's support services for bereaved and injured road crash victims.

Brake is calling for the Government to catch up with research and public attitudes by reducing the legal limit to 20mg alcohol per 100ml of blood - effectively zero tolerance.

The charity says this would send a clear message, in line with research, that driving after any amount of alcohol significantly increases crash risk.

Julie Townsend, deputy chief executive, Brake, said: "Public attitudes towards drink driving have shifted dramatically, yet people are still being killed and injured by those who continue to take this inexcusable risk.

“We need action from Government to rectify this and put a stop to the carnage that continues to result.

“Our current drink drive limit is a dangerous relic: research has shown a lower limit is far safer; hence almost all other countries in Europe have reduced theirs.

“Most people are on board with zero tolerance on drink driving, and the Government must respond. Reducing the limit to 20mg would send a clear message that any amount of alcohol before driving is a dangerous risk that's never worth it.

"We are also appealing to everyone to look after themselves, family and friends this festive season, by planning ahead to get home safely and speaking out against drink driving.

"If you drive, pledge to never drink any alcohol before getting behind the wheel, and if you have a designated driver, make sure they stay completely off the booze."

One in six deaths on UK roads are caused by drink drivers over the current legal limit, but drivers with even 20-50mg alcohol per 100ml of blood are at least three times more likely to die in a crash than those with no alcohol in their blood. This is because even small amounts of alcohol affect drivers' reaction times, judgment and co-ordination.

Alcohol also makes it impossible for drivers to assess their own impairment because it creates a false sense of confidence and means drivers are more inclined to take risks and believe they are in control when they are not.