Two of Britain's biggest supermarket chains have cut the price of diesel to 97.7p per litre, following the fall in oil prices.
Asda was the first to introduce the 2p reduction, saying it would take diesel to its lowest price in more than six years. Rivals Tesco announced they would match the 97.7p per litre price shortly after.
Oil prices have fallen by 30% since early December, with Brent crude sinking to less than 27 US dollars a barrel earlier this week.
Motoring groups welcomed the news, but said drivers had been waiting too long for a drop in costs, given the dip in oil prices.
A recent study by FairFuelUK found that, since May last year, oil prices have fallen by more than 54% but retailers have only cut pump prices by 35%.
The report said retailers' profit margin for diesel is 11p per litre compared with just 5.8p per litre for petrol.
A Tesco spokesman said it would continue to review prices "subject to changes in oil markets and foreign exchange movements".