Nearly three-quarters of drivers are worried about the effect of rising fuel costs, according to a survey by Post Office Car Insurance.
This is now the biggest concern for drivers.
In second place is the overall cost of running a car including maintenance repairs, breakdown cover, road taxes and MOTs, which 40% of drivers admit to being concerned about.
With costs at the forefront of drivers' minds many are acting to bring down the price of running a car. Almost half of the motorists surveyed (46%) admitted to making fewer journeys and 33% shop around for car insurance.
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A further third have cut back on their fuel purchases or shopped around for the cheapest petrol station in their area.
And motorists are also slowing down with 27% planning to cut their speed in a bid to conserve petrol.
"For many drivers, their car is their lifeline and many people rely on their car everyday.
With approximately 405 trips made by every driver each year and with the cost of fuel jumping 52% in the last five years, it is not surprising that motorists are becoming increasingly worried about rising fuel prices and the general cost of running their car," says Gerry Barrett, head of insurance at the Post Office.
The survey also revealed that more than half of motorists (66%) believe there should be a reduction in fuel tax, closely followed by 58% who want to see tougher laws on uninsured drivers as they drive up everyone's premiums.