ASDA sells the cheapest fuel in Britain, despite price pledges by many other suppliers, according to PHH Vehicle Management Services. As predicted by PHH in its July AllStar fuel price report average pump prices last month increased by more than the Budget-levied 4p a litre/18p a gallon and by the beginning of September had risen on average 5.4p a litre/25p a gallon over pre-Budget prices with peaks of more than 27p a gallon in some areas.

But, despite a narrowing of the massive fuel price differential around the country by an average of 0.96p a litre/4.4p a gallon last month, prices still vary greatly with differences of up to 5.4p a litre/24.4p a gallon around the country for unleaded petrol.

As a result Keith Greenhead, PHH divisional manager fuel, reminded fleets to shop around and warned that 'competitive price'-type schemes operated by oil companies which suggested ultra-competitive pricing tended to operate within a local area and may not be so attractive compared to national averages.

Highest and lowest fuel prices in August were: unleaded - lowest, Edinburgh 61.01p litre/ 277.35p gallon; highest, Aberystwyth 66.38p/301.76p. diesel - lowest, Glasgow 61.04p/277.48p; highest, Aberystwyth 66.23p/ 301.08p. 4 star - lowest, Swansea 66.79p/303.62p; highest, Aberystwyth 72.05p/ 327.53p.