Motorway service stations in Kent have been "ripping off" drivers by charging over the odds for fuel.

Maidstone services, on the M20 near Leeds, is among those accused of taking advantage of a captive market where motorists using such facilities have no choice but to fill up in an emergency.

It charges 165.9p per litre for diesel, putting it in the top 10 of the most expensive motorway service stations in the UK for that type of fuel, according to PetrolPrices.com.

Scroll down to listen to campaign group spokesman Kitty Bates

This is despite the nearest petrol station in Ashford Road, Maidstone, which is just over four miles away, selling it 30p a litre cheaper.

This equates to £12.60 more per tank if filling up at the services with a Ford Fiesta - the UK's best-selling car.

Medway services, on the M2, near Rainham, has also been accused of charging "extortionate" prices.

It sells petrol at 148.9p a litre, putting it in the top 10 of the most expensive motorway service stations in the UK for unleaded.

This is 24p per litre more than the nearest petrol station, Sainsburys in Hempstead, which is less than eight miles away.

This equates to £10.08 more per tank at the services, if filling up with a Ford Fiesta.

The figures have been issued by PetrolPrices.com to highlight the discrepancy between prices at motorway service stations and other forecourts.

The group's consumer spokesman Kitty Bates said: "Motorway service areas have long been overpriced because operators know that motorists have to fill up there, and they have a captive audience, so they charge a similar rate year round, regardless of the fluctuations in the wholesale industry.

"Their argument is the costs are higher, which is something the government has been saying that it wants to investigate for quite a few years now.

"However, until this takes place, we would encourage drivers to find the best fuel deal local to them, or along their intended route, before they set off using a fuel price checking service such as PetrolPrices.com which will help them to avoid being ripped off on the motorway.

"For too long millions of UK motorists have been stung by extortionate motorway service area fuel prices."

A statement on the Moto website, which runs Medway services, says: "We operate in a very different environment to most other retailers and once you see the costs of providing the facilities and services, the prices soon start to make sense.

"Despite the high cost of supplying these services, our commitment is to give our customers value for money at all times.

"In addition to the buildings, we also have to build roads, car parks, street lighting etc - an average site costs £25 million to build.

"We are open 24 hours a day and 365 days a year and for around half of that time we have to pay to be open (employee wages, power etc) when we are taking very little money and customers can use car parks, picnic areas, showers, washrooms etc all for free.

"Regulations mean we can't advertise on the motorway, so we have to rely on people simply turning in which affects how much business we get."

A spokesman for Roadchef, which owns Maidstone services, said: "Roadchef does not operate the petrol station forecourts at any of our service areas and does not set the price of fuel."

FairFuelUK founder Howard Cox said: "The greedy unchecked oil companies continue to ride roughshod over hard working low-income families who have no choice but to use their vehicles.

"Their rampant profiteering is most apparent in our motorway services."

The price of filling up your fuel tank is the highest it has been since 2014.

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