The UK's Competition and Markets Authority said Monday that sustained high fuel prices at the pump are being driven primarily by elevated wholesale costs, but warned that weak competition in the retail fuel market continues to leave motorists paying more than necessary.
The CMA, in its latest road fuel monitoring update, said higher pump prices seen through March and into April 2026 were largely driven by rising wholesale costs linked to geopolitical disruption, rather than by any change in retailers' pricing behavior.
The watchdog said fuel retail margins, the difference between wholesale costs and pump prices, remained historically elevated, averaging about 11.3 pence per liter in April, even as some supply conditions stabilized.
Though a small number of retailers saw margin increases in March, the CMA said this appeared to reflect competitive "follow-the-leader" pricing, inventory pressures and differing wholesale purchase costs rather than deliberate exploitation of the crisis.
There is no evidence that retailers altered their pricing strategies to take advantage of the crisis, the regulator said, adding that broader market conditions, including volatility and supply constraints, may have reduced incentives for aggressive price competition.
However, the CMA reiterated concerns over "weak competitive dynamics" in the UK fuel market, first identified in its 2023 review, saying many retailers continue to set prices passively by matching local competitors rather than competing to attract customers.
The CMA said supermarkets remained the cheapest place to buy fuel on average, while motorway service stations continued to charge a significant premium.
It also highlighted the potential benefits of price comparison tools under its Fuel Finder initiative, saying drivers could save up to 9 British Pounds ($12.11) per tank by shopping around.
Retailers should be in no doubt that we are continuing to monitor prices and margins closely, Sarah Cardell, chief executive of CMA, said, adding that any reductions in wholesale costs should be "rapidly and fully passed on" to consumers.
The regulator said it would closely monitor whether improved supply conditions in April are reflected in lower retail prices in the coming weeks.
The antitrust watchdog plans to publish its next update in August, covering market developments through the end of June, and will also conduct a deeper review of retailer pricing strategies, with findings expected in the autumn as part of an assessment of the Fuel Finder scheme's impact.