Supermarket gas costs have been roughly 5p costlier per litre in 2022 than pre-pandemic ranges, an investigation by the competitors watchdog has discovered.

The Competition and Markets Authority (CMA) has stated that components past the invasion of Ukraine have impacted the value clients are paying on the pumps and weak competitors has helped drive will increase.

Retailers, particularly supermarkets, got here in for criticism from the regulator.

"Higher pump prices cannot be attributed solely to factors outside the control of the retailers", the CMA stated.

Evidence supplied by the supermarkets, as a part of the CMA's highway gas market examine, additionally acquired criticism.

"Whilst the level of engagement with the study has varied across supermarkets, we are not satisfied that they have all been sufficiently forthcoming with the evidence they have provided," the CMA stated.

"In particular, important information has only been received late in the day and after several rounds of information gathering.

"Given the issues now we have a couple of market of such significance to thousands and thousands of drivers it's critical we resolve what's going on."

In an effort to "get to the center of the problems", the CMA will conduct "formal interviews" with the senior administration of supermarkets.

The CMA did add that supermarkets nonetheless are typically the most cost effective retail suppliers of gas however discovered proof indicating "at least one" grocery store has "significantly increased" its inner forward-looking gas margin targets.

Other supermarkets have recognised this and should have modified their pricing behaviour accordingly, the regulator stated.

Concern was additionally expressed over doable proof of weaker competitors in diesel in comparison with petrol because the begin of this yr.

High diesel margins seen this year "appear to have gone on longer than would be expected", the physique stated, although some extent of variation is to be anticipated given risky diesel wholesale costs.

Competition amongst petrol forecourts has declined. In March of this yr the CMA recognized 13 areas of concern as a part of Asda's plan to purchase Co-op petrol stations and requested the grocery store purchaser take remedial motion.

The watchdog has additionally been investigating value rises within the grocery market and on Monday introduced it's stepping up its work to see if there are any competitors failures which can contribute to costlier grocery costs.

So far the physique stated world components have been the principle driver of grocery value will increase and it has not seen proof of particular competitors issues within the sector.

"The CMA acknowledge that higher prices are a result of global price increases, resulting in high food inflation both in UK and across Europe," the director of meals and sustainability on the British Retail Consortium (BRC) stated.

"British supermarkets are confident that they are doing all they can to keep food prices as low as possible for consumers, and we have seen margins squeezed across the industry."

"The UK has one of the most competitive markets for food in the world, and as global prices begin to fall we are confident that the competitive nature of the industry will help food inflation fall as a result," Andrew Opie added.

The Petrol Retailers Association have been contacted for remark.