When the Chancellor of the Exchequer, Gordon Brown, announces his budget on Wednesday, it's likely that owners of the heaviest polluting cars will face substantial increases in road tax.
Cars in pollution band G, which includes many 4x4s and sports cars, could pay twice as much as they do now, according to some reports.
At the last budget, a higher rate of Vehicle Excise Duty (VED - road tax) was introduced, which meant that heavily polluting cars paid £210 per year. Now, it's possible they'll pay double - up to around £400 a year.
Instead of the increases coming in immediately, though, it is thought they will be brought in over two years.
The Chancellor is believed to want to use the tax system to encourage car buyers to choose more environmentally sound vehicles by increasing VED in this way, rather than simply pricing such cars off the road.
Our reviews are based on hard data and thorough testing in the real world.
Up to the minute news from around the globe
Get a car insurance quote from over 100 companies with What Car? Compare in less than five minutes
What Car?
is brought to you by
Haymarket Consumer Media