The price of diesel in the UK has shot up at one of its fastest rates in more than 20 years – while retailers have been accused of charging “unjustifiably” high petrol prices.
Diesel prices rose by more than 8p a litre to 163p in September, the fifth biggest monthly rise since 2000, and on top of another 8p rise the previous month, the RAC said. Petrol prices rose by 4.5p a litre to 152p, the fourth consecutive monthly increase.
The increases come after the extension of global oil production cuts from Russia and Saudi Arabia, designed to bolster prices, pushed up oil prices to almost $100 (£82.89) a barrel in September, feeding through to prices at the pump.
The supply constraints combined with the weaker value of the pound – making wholesale fuel, which is traded in dollars, more expensive to buy in the UK – have pushed up prices.
Brent crude, the oil price benchmark, rose to a 10-month high last month of almost $98 a barrel, up from $72 a barrel at its lowest point in June, representing its biggest quarterly increase since Russia’s invasion of Ukraine.
As a result, drivers have been forced to pay almost £90 to fill up a 55-litre family diesel car – the highest cost since April – and more than £86 for a similar petrol car, the highest cost since December 2022.
The pain at the pump comes on top of high inflation for most household goods, and the prospect of another winter of high energy bills.
Oil prices have eased in recent weeks in response to a strengthening US dollar, with Brent crude trading at about $90 a barrel.
However, the RAC said its analysis suggested that petrol was “overpriced by about 7p a litre”.
The RAC fuel spokesperson, Simon Williams, said: “In the last two weeks the wholesale cost of diesel has become 10p a litre more expensive than petrol, yet the gap at the pumps is only 5p. If retailers as a whole were playing fair with drivers, petrol would be at least 7p cheaper than it is now, down to about 150p from its current average of 157p.”
Fuel retailers and supermarkets have been accused of using motorists as “cash cows” and earlier this year the Competition and Markets Authority (CMA) found that drivers were paying more for petrol and diesel than before the Covid pandemic because of “weakened” competition.
After the CMA’s intervention, retailers will be forced to provide live pricing data, allowing drivers to more easily shop around for the best fuel deals.
Williams said: “It’s worrying that retailer margin across the UK is higher for petrol than it should be, considering the big four supermarkets were told off by the CMA for overcharging drivers by £900m in 2022.
“While many have voluntarily started to publish their prices ahead of being mandated to in law, we still have a situation where wholesale price changes aren’t being fairly reflected on the forecourt.”
This week Haitham al-Ghais, the secretary general of the Opec+ group of 23 oil-producing nations, which includes Russia and Saudi Arabia, said he expected demand for oil to grow and remain “resilient” this year.