The average price of diesel in Britain jumped to 191.69p per litre on Monday, according to the RAC, overtaking the previous high of 191.54p recorded on April 15. The RAC has warned that diesel is now on track to reach £2 a litre for the first time.
The motoring group linked the rise to the ongoing conflict in the Middle East, which it said has severely affected fuel supplies through damaged refineries and disrupted shipping lanes through the Strait of Hormuz, one of the world's busiest oil transit routes.
At current prices, filling up a 55-litre family diesel car now costs more than £105.
RAC warns of 'Iran War highs'
Simon Williams, head of policy at the RAC, said: "Fuel prices hit new Iran War highs on Monday. Both fuels are now at prices last seen in early August 2022, just a few months after the start of the Ukraine War, following price rises of 8p a litre since the start of September."
He added: "And with oil well over $100 a barrel, there's no end in sight to high pump prices and the pain it brings to drivers who depend on their vehicles. In fact, the average price of diesel may be on the way to overtaking the record high of 199.05p set on 25 June 2022."
Williams noted that petrol "is still a long way from its all-time record of 191.53p on 3 July 2022."
Rod Dennis, also from the RAC, said last week: "We expect diesel prices to hit a new US/Iran war high within days." He urged motorists to shop around rather than be caught out at the pump.
Small businesses feel the strain
Tina McKenzie, national chair of the Federation of Small Businesses, warned that rising diesel costs would hit firms that depend on vans and lorries. "The vast majority of vans and heavy goods vehicles run on diesel, so if pump prices spiral even higher, countless small business owners and self-employed people will feel the hit to their margins," she said.
She added: "Higher diesel prices will mean higher prices for all kinds of goods and services, sooner or later. With businesses and households alike already having to cope with cost pressures, higher diesel costs will add fuel to the flames, suppressing growth prospects and impacting on consumer spending."
McKenzie said more than half of small firms now cite fuel as a driver of cost rises, double the proportion reported at the same time last year. "The prospect of this situation getting even worse is not a welcome one for the small business and self-employed community, who rely on their vans and lorries to get on with the job," she said.
How prices have climbed since February
The scale of the increase has been steep. Diesel stood at 142.38p a litre at the end of February, meaning the near 50p-a-litre rise since then represents a 34 per cent increase over seven months.
Unleaded petrol has followed a similar path, rising from 132.83p in February to a price now 27 per cent higher, though it remains below its 2022 record.
The Federation of Small Businesses represents small and self-employed business owners across the UK, while the RAC is one of Britain's leading motoring organisations, regularly tracking pump prices and advising drivers.
