The International Energy Agency has released 400 million barrels of crude from strategic reserves since March, and Executive Director Fatih Birol says another release — while not the priority today — remains on the table if supply disruptions worsen before winter.

Speaking at a meeting of EU energy ministers in Dublin, Birol said the volumes drawn so far equal 20% of overall stocks, and one-third of the released barrels have yet to reach the market. "80% is still in our pocket. If there is a need and if our member countries do agree with it, we are ready to act in order to address current and future market challenges," he said. He also stressed that further releases are "not the number one agenda for the IEA".

What is driving the renewed supply pressure?

Europe has spent more than €100 billion extra on energy imports since the outbreak of the war in Iran, EU Energy Commissioner Dan Jørgensen told ministers on Tuesday — and despite that outlay, the bloc has received "not one extra molecule of gas or oil".

The disruption sits at the Strait of Hormuz, which carried roughly a fifth of globally traded oil before the war. Tightened flows through the waterway have squeezed both crude and diesel supplies worldwide, and Europe — structurally short of diesel — sits at the sharp end.

"Europe is one of the most exposed regions — if not the most exposed one — when it comes to diesel because Europe imports a huge amount of diesel and we are entering the harsh season, the winter season," Birol said.

The exposure has a recent history. After EU sanctions on Russian oil products took effect in 2023, Europe shifted its diesel sourcing toward the US. In August, the US supplied around half of the EU's diesel imports. That dependence now looks fragile, because Washington is weighing export restrictions of its own — a move the European Commission has already branded a "bad idea" that would hurt both economies.

What could a US diesel export ban cost Europe?

Oxford Economics calculates that a full US ban could lift European wholesale diesel prices by 40% to 50%. If passed through to consumers, that would add €0.50 to €0.60 per litre, including VAT, and a few tenths of a percentage point to inflation. Those figures model a full ban, not the narrower restrictions US officials have also discussed; scope, duration and exemptions remain unclear.

Replacement barrels would not arrive quickly. Oxford Economics points to constrained Middle Eastern supply and notes that diesel from Asian refiners needs longer voyage times to reach Europe. The firm also expects Europe could tap emergency reserves if US restrictions drove prices higher, potentially capping the increase.

For fuel buyers and road carriers, the pressure is already visible. The EU's average diesel price hit a record €2.23 per litre last week. France posted €2.40 per litre and Denmark €2.56 on Tuesday last week.

Why do US refiners oppose the ban?

The idea faces resistance inside the US as well. In a 23 September letter to President Donald Trump, the Business Roundtable, the American Petroleum Institute and more than two dozen other groups warned that refiners forced to keep surplus diesel at home might have to cut production — which would also reduce petrol and jet fuel output.

Kpler data underline the physical constraint: US refineries ran above 95% of capacity for much of the summer and hit roughly 98% in the final week of August, leaving virtually no headroom to raise output. Kpler says keeping exported diesel in the US could initially lower Gulf Coast prices, but storage and transport bottlenecks would make it hard to spread that relief nationwide, and weaker refining margins could eventually push producers to cut runs.

Oxford Economics estimates a full ban could cut US diesel prices by roughly 30% within weeks — but warns the same storage problems and reduced refinery runs could raise petrol and jet fuel prices, offsetting part of the benefit for American consumers.

What happens next?

Ireland's energy minister, Darragh O'Brien called a US ban "unlikely" because it would damage economies on both sides of the Atlantic, but urged the EU to prepare regardless. "We have to be guarded. We can't be complacent," he said.

Jørgensen, for his part, pushed for faster investment in electricity and power infrastructure to cut the bloc's reliance on imported fossil fuels. With Hormuz flows disrupted, US export policy unresolved and winter demand approaching, the IEA's untouched 80% of strategic stock looks increasingly like the market's last buffer.