Anyone who drives a diesel car has been warned that they could be facing higher fuel prices than those who have petrol vehicles.
Motoring group the RAC explained that even though the wholesale cost of diesel is declining, it still remains about 16p more expensive than it should be - meaning drivers are being overcharged by £9 every time they fill up.
At the end of April, diesel was actually cheaper than petrol, coming in at 6p cheaper per litre. However, this wholesale price wasn't reflected at the pump, with a litre of diesel costing 159.43p on average compared to 146.5p for petrol.
The Mirror reports that a litre of wholesale diesel cost 104.88p on April 28, down 9p in the month, and unleaded was 111.25p, down 6p.
And the RAC thinks that drivers should be paying around 143p “at the very most” for a litre of diesel, saving drivers a huge £9 per tank.
The latest information from the RAC shows the cost of filling a 55-litre family car with petrol now stands at £80.60, or £87.69 for diesel. Prices are slightly lower in Northern Ireland, where diesel averages 147.47p.
At the end of April, the average price of unleaded petrol at one of the four major supermarkets was 142.99p, working out at 3.5p cheaper than the UK average.
Diesel was 2.75p cheaper than the average at 156.68p – down 3p since the start of the month.
RAC fuel spokesman Simon Williams said: "Diesel drivers across the UK mainland continue to lose out badly at the pumps. They’re paying 13p a litre more for the fuel than petrol, despite diesel being cheaper for retailers to buy on the wholesale market for all of April.
"This just isn’t fair for the country’s 12m diesel car drivers. We feel there should be an obligation on retailers to reflect wholesale price movements on their forecourts. "
He added: "Action at a government level is badly needed to stop drivers being ripped off any longer.
"While we’re not in favour of prices being capped – as we feel this could lead to smaller retailers in rural areas not being able to compete and going out of business to the detriment of the communities they serve – we feel there should be an obligation on the biggest retailers to charge fairer prices in relation to wholesale market movements."
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