Some supermarkets have been charging drivers 6p more per litre of fuel, costing motorists £900m in a single year, a government watchdog has found.

In response to the findings, the government is preparing to force retailers to publicly state how much they are charging at the pump, so that drivers can compare prices in real time.

The government will change the law to force retailers to comply by providing up to date price information, which is expected to lead to greater transparency and competition – in turn driving down prices and easing people’s cost of living.

The new scheme will make pricing data available for third parties – paving the way for them to create price comparison apps and websites.

Brentwood Live: Some supermarkets have been charging drivers 6p more per litre of fuel, with new rules being introduced by the government in responseSome supermarkets have been charging drivers 6p more per litre of fuel, with new rules being introduced by the government in response (Image: Getty)

The action follows publication of a Competitions and Markets Authority (CMA) report showing some supermarkets charged drivers 6p more per litre for fuel. This amounts to £900m in extra costs in 2022 alone - around £75m a month.

Grant Shapps, Energy Security Secretary, said: “Some fuel retailers have been using motorists as cash cows – they jacked up their prices when fuel costs rocketed but failed to pass on savings now costs have fallen.

“It cannot be right that at a time when families are struggling with rising living costs, retailers are prioritising their bottom line, putting upwards pressure on inflation and pocketing hundreds of millions of pounds at the expense of hardworking people.

“Today I’m putting into action the CMA’s recommendations and standing by consumers – we’ll shine a light on rip-off retailers to drive down prices and make sure they’re held to account by putting into law new powers to increase transparency.”

Jeremy Hunt, Chancellor of the Exchequer, said: “It isn’t fair that businesses are refusing to pass on lower prices to protect their profits while working people struggle with balancing their budgets.

“Consumers need to be treated fairly, and so we’re empowering drivers to find the best prices possible for their fuel by taking swift steps following the CMA’s recommendations.”

The CMA’s report found a concerning weakening of competition in the fuel market and an overall increase in retailers’ margins, especially in respect of diesel and with supermarkets the worst offenders.

It also noted a lack of reliable and comprehensive price information available to motorists.