Shell was the latest major oil company to cut its fuel prices today, coming in line with supermarkets Asda and Tesco as well as its biggest rival petrol companies.
The price war was in full swing as prices fell by as much as four pence in some areas, after a drop in the wholesale price of oil. Shell, which has about 900 filling stations across the country, will cut its prices by between two and four pence per litre by the end of the day, a spokeswoman said.
"We will reduce our price of fuel in line with recent reductions in the internationally-traded wholesale price of petrol in the UK," she said. "We are determined to remain at the competitive forefront of pricing across the UK."
The spokeswoman said the fuel reduction would apply to both unleaded fuel and diesel. Petrol giant BP was also expected to enter the fray this weekend, after it announced that it was likely to make "unspecified reductions on the forecourt".
Rival Esso has also pledged to drop its prices. A Treasury spokesman said the Government would not be complacent about its efforts to bring down world oil prices, and stabilise the market for the long term.
The AA Motoring Trust also welcomed the cuts, but said UK motorists were still spending £7.5 million extra per day on petrol in comparison to figures for January.
The latest news is likely to further frustrate motorists who rushed to fill up their tanks at inflated prices in the run-up to anticipated protests outside refineries on Wednesday, which in the end saw only low turnouts and caused no disruption to supplies.
Chris Hunt, from the UK Petroleum Industry Association, said: "I think it is rather unfortunate that motorists filled up in panic buying when they will find it four pence cheaper now." Asda and Tesco were the first to cut the price of fuel by up to four pence a litre.
A litre of unleaded on Asda's 158 forecourts dropped to 89.9p compared with this year's record high of 93.9p, while diesel fell to a maximum price of 92.9p per litre.
Asda has pledged to publish its maximum prices on its website - www.asda.com - and is challenging other forecourt operators to do the same.