The price of petrol is dropping at supermarket forecourts once again as Asda, Sainsbury’s, Tesco and Morrisons announced a cut in prices from tomorrow.

Asda has guaranteed customers a national price cap of 133.7p per litre at its 217 forecourts. “From Tuesday, everybody filling up at an Asda fuel station will pay no more than 133.7 pence per litre for unleaded and 137.7p for diesel, unlike some of our competitors whose postcode lottery pricing means prices can vary across their forecourts by up to six pence per litre,” said Andy Peake, petrol trading director.

Richard Crampton, Sainsbury’s head of fuel, said: “We’re always looking for ways to help customers save money so from tomorrow we will be reducing the price of unleaded at our 280 forecourts by up to 2p per litre.”

Announcing the cut, Peter Cattell, petrol category director at Tesco, added: “From this week our customers can get twice the amount of Clubcard points when they buy Tesco Momentum99 unleaded petrol, another way in which we are offering our customers a helping hand.”

Morrisons also said it would cut 3p off the price of a litre of petrol.

Last week supermarkets cut the price of diesel by 2p a litre.

Recent figures showed that supermarket fuel sales remained flat in 2012 despite a major programme of forecourt openings and promotional activity.