Petrol prices at the pumps are not falling fast enough and in line with wholesale price drops, according to the RAC.

Over the last eight weeks, the average price paid for unleaded by drivers across the UK has only dropped by 9p a litre– all of which came off in July – despite wholesale petrol prices falling by 20p in the same time period.

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According to the motoring organisation, the wholesale cost of unleaded is now back to the prices reached in early May, meaning a litre should be 167p, not 183p. The disparity in cost from wholesale to consumer means drivers are paying nearly £9 more on a tank of petrol than they should be, it said. A tank of diesel should be lower than the end of July average, the RAC added.

July has been an unnecessarily tough month for drivers due to the big four supermarkets’ unwillingness to cut their prices to a more a reasonable level, reflecting the consistent and significant reductions in the wholesale cost of petrol and diesel,” said the RAC fuel spokesperson, Simon Williams.

Williams added that it was independent retailers and not supermarkets that led the way for fairer prices across the country, which forced supermarkets to bring prices down.

“The best advice for filling up is no longer to assume the supermarkets are the cheapest, but to shop around as it’s highly likely you’ll find an independent retailer which is doing the right thing and fairly reflecting their lower wholesale costs by charging a lower price,” Williams said.