Sainsbury’s has sparked a supermarket price war on fuel after an announcement it was cutting its prices was rapidly followed by Asda and Tesco also announcing cuts.

It began yesterday when Richard Crampton, Sainsbury’s head of fuel, said that from today Sainsbury’s petrol prices will drop by 4p per litre across its 279 forecourts, with diesel dropping by 3p per litre.

Asda then responded by announcing it would be cutting its petrol by up to 3p a litre and its diesel by up to 2p a litre, adding that drivers would pay no more than 134.7p a litre for petrol and 141.7p a litre for diesel.

A short time later Tesco also reacted with a 3p price cut at its 496 forecourts.

The AA welcomed the move. AA head of public affairs Paul Watters said: “This is a substantial fall, worth £2 a tank of petrol, and fairly reflects the drop in wholesale costs which started in late February.

“However, many non-supermarket fuel stations started undercutting supermarket prices a fortnight ago.”

The price cuts come a week before the Budget when a wide coalition of groups have been pressing for the Chancellor to abandon the duty rise scheduled for September.