All four major supermarkets have cut petrol prices for the second week in a row, amid an increasingly intense fuel price war.

Asda led the onslaught yesterday, announcing that unleaded would fall by 2p to 111.9p per litre, and diesel will drop 4p to 124.9p across all its 171 forecourts today.

Tesco brought in cuts of up to 2p per litre on petrol and 4p on diesel yesterday afternoon at the store’s 430 petrol stations. At its Burnt Tree island filling forecourt today diesel cost 124.9p a litre and unleaded 111.9p.

Then Morrisons stepped in, announcing price drops on petrol by 2p a litre and diesel by 4p a litre on its 285 forecourts. Sainsbury’s also pledged to slash petrol by up to 3p and diesel by 4p today. Retail giant Asda continued on the offensive by challenging other major supermarkets to set prices nationally rather than locally, which it says will mean a better deal for drivers.

Asda trading director David Miles said: “At Asda, you pay the same low fuel prices whether you’re in Elgin or Eastbourne.

Tesco, Morrisons and Sainsbury’s said they price their fuel locally and compete on cost within each area.BP also lowered prices yesterday by up to 3p at a number of its sites and will continue to review costs throughout the week, a company spokesman said.