Consumer watchdog Which? has warned motorists in the UK to watch out for inflated fuel prices at motorway service stations.
The watchdog found in its study that a litre of unleaded petrol costs 6p more on average, and diesel 7p higher, at motorway forecourts compared with fuel stops away from the motorway.
This adds almost £5 to a 70-litre diesel tank.
The report also found major variations in prices of basic necessities such as bottle water, sometimes even within the same service station.
The cheapest 500ml bottle was found to cost 75p, while the most expensive was £1.99.
Richard Lloyd, executive director ofWhich?, said: "One in two families have decided to holiday in Britain this summer, but they'll need to watch out for pumped up prices at motorway service stations. Not only are petrol and basic necessities like water more expensive, they'll even be charged to take their own money out at a cash point."
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