Satellite navigation systems are being blamed for 300,000 road accidents each year, according to research by DirectLine for the Daily Mirror.

The research found that over half of drivers now use satellite navigation devices which are causing increasing problems on the road.

Over 1.5 million drivers said that they had driven badly because they were consulting the devices, either by veering across lanes or making illegal manoeuvres.

"If a sat-nav gives you an instruction that is likely to endanger other road users, ignore it," said Maggie Game of Direct Line.

"Motorists must realise that, while they are a helpful navigation tool, they should not follow their instructions to the detriment of road safety."

One in 10 drivers said that the systems had caused them to make an illegal turn, double that number had lost track of traffic because they were distracted and one in four had been sent the wrong way down a one-way street.

Psychology professor Cary Cooper of Lancaster University said: "Some people are easily persuadable and will follow instructions, whether it is their wife or a computer telling them where to go.

"Even when information is being fed back to them, such as road signs that suggest they're on the wrong route, they won't believe it. They only admit mistakes when they're being winched out of a gully."