Petrol and diesel retailers today defended rising prices at the pumps at a time when the cost of crude oil was falling.

They insisted they were not exploiting motorists, blaming the weak British pound against the US dollar for the situation.

Their comments follow a Shropshire Star investigation which revealed wildly fluctuating prices at the pumps. Unleaded fuel varied from £1.31 to £1.46 yesterday, while diesel ranged from £1.36 to nearly £1.50.

Some forecourts were close to their highest ever prices, despite a sustained fall in the cost of crude oil over the past four months.

Brian Madderson of RMI Petrol, which represents independent forecourts across the UK, said the fact that an average of 500 filling stations were closing each year showed there was little money to be made.

“If they were making substantial margins, we would see more investment coming into the business, rather than going out of it,” he said.

Although the price of crude oil had fallen, Mr Madderson pointed out that it was sold in US dollars, and with the British pound weakening against the dollar, the price was being pushed up.

“As a result we are not getting as much of the saving from crude oil prices as might be expected,” he added.

Most independent forecourts make between two and four pence profit on a litre of fuel – meaning a full tank only earns the petrol station between £1 and £2.

Mr Madderson said that was “hardly sustainable”, and explained petrol stations needed to add on extra revenue-earning services, such as shops, car washes or cash machines.

The cost of Brent crude oil has fallen by around 18 per cent since the start of April, but the cost of a litre of unleaded fuel has risen in that time by 1.8 per cent.

In addition to exchange rate troubles, the petrol industry said it was also being hit by rising delivery charges – ironically, largely due to the rising cost of fuel.

Shropshire’s supermarkets this week began their latest fuel price war, with Asda, Morrisons and Tesco cutting 1p or 2p off the price of a litre.

By Carl Jones