Business drivers who fuel up at Gloucestershire supermarkets are being ripped off to the tune of 5p per litre, according to latest research from the RAC.

In the wake of the government's 5p duty cut, which came in last year, Russia's invasion of Ukraine pushed prices up. But wholesale prices are now lower by almost $20 per barrel and, despite this, drivers who need petrol and diesel are not seeing that benefit on the forecourts.

RAC fuel spokesman Simon Williams said: "Drivers are still losing out massively when wholesale prices come down. But in Northern Ireland, where the supermarkets don't dominate fuel retailing, drivers are getting a fairer deal with a litre of unleaded costing 150p and diesel 157p - 5p less than the UK average."

Calling for the biggest fuel retailers to strike parity with Northern Ireland, the motoring body sais that the big four supermarkets - Tesco, Morrisons, Asda and Sainsburys - are making the most profit from petrol. Collectively, their alleged unfair share was an average of 16p for every litre of unleaded fuel sold in October, while they make an extra 12p profit for every litre of diesel.

The RAC also calculates that the profit on unleaded fuel is now double the average the supermarkets had been making since 2012.

In response, Asda stated that its prices are around 4p per litre cheaper than the UK average. Tesco, Sainsburys and Morrisons have not commented on the claims.

The RAC criticism comes in the wake of an investigation by the Competition and Markets Authority (CMA) as reported in July , which showed that supermarkets had overcharged diesel and petrol customers to the tune of £900m in 2022. Retailers had passed on Chancellor Jeremey Hunt's 5p reduction, but rising profit margins had swallowed the benefit.

At the time, the government promised to take action and mandate for live pricing but indicated that the system would require legislation which, as yet, has not appeared.

In the meanwhile, the RAC has established its own fuel monitoring app and also publishes updates on latest pump prices online.