Petrol-diesel price gap growing: AA
The gap is biggest in Scotland, with petrol 8.2p a litre cheaper than diesel on average.
Regionally, the most expensive petrol is being sold in London, averaging 134.8p a litre, while diesel is dearest in Northern Ireland at 141.8p a litre. Yorkshire and Humberside is the cheapest region for both, averaging 132.8p for petrol and 140.3p for diesel.
AA president Edmund King said: "The fall in the price of oil due to the eurozone crisis had brought some hope of respite for drivers but the opposite has happened for diesel car owners.
"The petrol price may have been falling overall, but it's dropped faster for some than others, and that adds to the frustration."
He went on: "Tuesday's House of Commons debate on high fuel prices offered little hope of a freeze in fuel duty, and diesel woes, if they continue, will intensify pressure on the Treasury.
"It may help them to note that the 15p a litre higher price of petrol and 18p for diesel, compared to a year ago, includes respectively a 2.5p and 3p-a-litre VAT windfall - if they're still wondering how to finance the freezing of January's 3.02p fuel duty increase."
© 2011 Press Association