A difference of nearly 10p in fuel prices was being sold at two Medway service stations - just a mile apart.

At the Moto garage on the M2 in Gillingham, known for having some of the most expensive fuel in the country, unleaded petrol was priced at £1.42.9p while diesel was going for £1.47.9p.

Down the road at the Mace garage in Hoath Lane, drivers were paying £1.33.9p for unleaded and £1.36.9p for diesel.

While the Esso garage in Gibraltar Hill, Chatham, is selling its unleaded petrol for £1.29 per litre - almost 14p less than the Moto garage.

Under a new government law to stamp out petrol profiteering, the huge discrepancy in charges could become a thing of the past.

Motorway signs displaying pump prices of several nearby stations will warn unsuspecting drivers, and give them the option of driving on to fill their tanks up with cheaper fuel.

The tough new measures come after an official investigation into petrol prices by the Office for Fair Trading, which found motorway service stations were selling petrol for 7.5p litre above average price with diesel going for an extra 8.3p a litre.

Although no date has been set for the legislation, it is being treated as a top priority by Downing Street’s policy unit.

Another option being discussed is adopting a system used in France where petrol stations are ordered to show petrol prices of their main rivals.

The announcement has been welcomed by motorists who rely on driving to make a living.

Jeremy Fox, who runs the Elite School of Driving in Rochester, said: “It’s a great idea. I try and come off the motorway when I need petrol. But, I have been caught out and have had to pay through the nose.

"It’s always the motorist who is ripped off.”

Paul Burridge, commercial director of Strood-based R Swain and Sons haulage company, said: “Anyone who is daft enough to fill up at a motorway service station is asking to be fleeced.

"But if you do get caught out, then I welcome anything that might stop them from charging such high prices.”