Petrol prices at the pumps are not falling in line with wholesale price drops, with the cost of a full tank of petrol only £5 cheaper in July, according to new data.
Average petrol prices dropped by nearly 9p over the month to 182.69p per litre, while diesel fell by almost 7p to 192.38p per litre, according to the RAC.
The RAC said nearly £5 was shaved off the cost of a 55-litre tank of petrol in July, from £105.29 down to £100.48, as retailers lowered their prices. The cost of filling up a diesel tank dropped by £3.68 over the month.
But the motoring group warned the reductions still don't fairly reflect the fall in the wholesale price of fuel.
The wholesale cost of petrol has fallen by 20p since early June, according to the RAC fuel watch analysis.
Yet UK retailers continued to increase their prices in June and only dropped their pump prices by an average of 9p during July, the motoring group said.
This means drivers filling up at the end of July paid almost £9 more per tank more than they should have.
RAC fuel spokesman Simon Williams said the biggest retailers should have "cut their prices more significantly on a daily basis", given the steady and consistent fall in the wholesale price of petrol.
He said their unwillingness to do this made July "an unnecessarily tough month for drivers".
The “big four” supermarkets — Tesco (TSCO.L), Asda, Morrisons and Sainsbury’s (SBRY.L), along with several other suppliers — have been facing criticism for failing to reduce their prices in line with falling wholesale costs.
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.
Fuel prices have soared in recent months, driven by the war in Ukraine and moves to reduce Europe's dependence on oil from Russia.