Cardell said the CMA would stay “vigilant” to ensure any fall in wholesale costs is passed onto drivers.
The CMA also said there were significant local variations in price, with potential savings of up to £9 per tank of petrol and diesel if drivers shop around.
In March, the CMA said it would be considering how quickly fuel prices rise and fall as wholesale costs change, and whether there was evidence of so-called “rocket and feather” pricing.
It previously found evidence of such pricing following Russia’s invasion of Ukraine in 2022, external, with prices going up quickly when wholesale prices increased, but falling more slowly when wholesale prices dropped.
The AA said the wholesale cost of diesel had fallen by more than the price at the pumps, while drivers were paying up to 20p more for petrol on motorways than they were on A-roads.
Luke Bosdet, the AA’s spokesman on pump prices, said: “Maybe not price gouging, but ‘rocket and feather’ and the pump-price postcode lottery are as strong as ever.
“The competition watchdog still has a lot of work to do.”
The regulator also said in March it was examining heating oil prices, external after it received a “number of concerning reports from consumers who rely on heating oil about their experiences with retailers”.