Drink or drug driving is a problem all year round and not just at Christmas, West Midlands Police warned yesterday.

The announcement came after the force said more people tested positive for driving under the influence of alcohol or drugs during the summer last year than they did during the winter.

From June to September 2004, a total of 1,477 drivers were stopped by the police. Of them 211, or 14 per cent, tested positive for drink or drugs.

Over the Christmas period, 2,547 people were stopped. A total of 239, or nine per cent of those stopped, tested positive.

While the number of people tested during the summer period was lower than the number tested over Christmas, more people tested positive which sparked police to re-issue warnings to drivers.

Sergeant Steve Rogers, West Midlands road policing officer, said: "Drink driving and drug driving remains a problem all year, but with the warm weather, outdoor parties and more relaxed atmosphere during the summer, the temptation is again greater.

"Passengers can help by refusing to be driven by someone who has been drinking or taken drugs, and by appointing a designated driver who does not drink or take drugs."

More than 400 people will be killed as a result of drink driving this year.