Motorists will get a boost as Asda, Morrisons, Sainsbury's and Tesco are cutting both unleaded and diesel prices this week.

Asda is cutting the price of unleaded by up to 2p a litre and diesel by up to 1p a litre from tomorrow, while Morrisons is dropping the price of unleaded by up to 2p a litre and diesel by 1p a litre from 3pm today.

Sainsbury's is cutting the price of both unleaded and diesel by up to 2p a litre from tomorrow. Tesco will introduce the same price reductions as Sainsbury's, but from this afternoon.

The move is the latest in a series of reductions by supermarkets over the last few weeks (see our Cheap Petrol and Diesel guide for tips on driving down costs).

Prices vary locally at Morrisons, Sainsbury's and Tesco, but Asda says motorists will pay no more than 129.7p per litre for unleaded and no more than 134.7p per litre for diesel at its pumps from tomorrow. 

However, the latest reductions won't necessarily mean any of these supermarkets will be the cheapest fuel provider. The website Petrolprices.com lists the cheapest in your area.

On Tuesday, the average price of unleaded was 134.79p and 139.27p for diesel, according to the site.

Unleaded prices rose from an average 132p a litre in December to 140p a litre in March according to the AA, but prices have since fallen. The AA predicted last month that average unleaded prices could slip to about 134p a litre soon, thanks to wholesale fuel prices dropping.

Additional reporting by the Press Association.