UK motorists are set to face £2-a-litre diesel prices within days, an oil products expert has warned, as wholesale prices surge to a four-year high. Alan Gelder, from Wood Mackenzie, said diesel prices at UK petrol stations were expected to surpass £2 a litre within a week after European diesel futures reached the equivalent of $211 (£160) a barrel – almost double the price of crude oil.

While the closure of the Strait of Hormuz to the vast majority of tankers has driven up oil prices worldwide, resulting in increases in jet fuel and petrol costs, it is diesel that has seen the most significant gains as buyers fight for remaining supplies. “Every day that passes, the oil market gets tighter, so prices continue to climb,” Mr Gelder said. “Diesel prices could well go much higher.” Last month, the UK saw the highest monthly rise in petrol and diesel prices on record, according to figures compiled by the RAC.

The cost of unleaded petrol at the pump rose by 20p a litre and more than 40p for diesel last month. Diesel is selling for an average of £1.85 a litre, according to RAC data.

Since 2022, Middle Eastern refiners have become increasingly significant to European diesel supplies, following restrictions on purchases from Russia following the invasion of Ukraine.

“Fuel prices have never risen this fast in a single month,” RAC head of policy Simon Williams said. “The increases drivers have had to endure in March 2026 far exceed those seen in the early days of the war in Ukraine.”

While UK imports only about a tenth of its own diesel supplies directly from the Middle East, about 40% of its stock comes from Dutch and Belgian refineries, which get a significant portion of their crude from the region.

On top of this, Asia is increasingly outbidding Europe for vital diesel supplies, causing tankers to divert to the Far East.

At least six Europe-bound ships carrying US diesel have rerouted to Asia since the Iran war began, according to Kpler, as Asian buyers are willing to pay more due to their usual reliance on Middle Eastern supplies.

“We’ve even seen a few cargoes loading out of Europe and heading towards Singapore – Europe is itself short of diesel and should be importing, but the prices are screaming right now that Asia needs it so much more,” said Philip Jones-Lux, senior analyst at Sparta Commodities, according to the FT.

This fresh warning comes as Brits have been urged to open their windows at certain speeds amid the fuel price spike. With drivers looking to keep the costs of running their cars down, vehicle security firm Lock & Track have shared various tips for making your vehicle more energy efficient, also including driving at speeds below 45mph.

“Once you exceed 45mph, the aerodynamic drag caused by an open window outweighs the energy required to run the air conditioning compressor,” the firm wrote in a blog on its website.