Middle East: the war has become leverage — diesel, Europe, China

Seven months after the first US-Israeli strikes on Iran, the war has produced neither a winner nor a settlement. It has produced something else: a price. And since the UN rostrum on 22 September, that price has visibly been serving a purpose other than bending Tehran. Here is what is established, what is reported, and what is only a scenario.

What was said at the UN

On 22 September, before the United Nations General Assembly, Donald Trump put the choice bluntly: either a deal with Iran or, in his words, annihilating the Islamic Republic and sending it "to hell". The line made the headlines. It is not, however, the most informative part of his speech.

A president who publicly names the month in which he intends to conclude also announces, by implication, the number of weeks during which he will not. Between 22 September and 3 November, the war is not a problem to be solved: it is a stable backdrop. And in energy markets, a stable backdrop is called a risk premium that does not deflate.

The weapon that does not fire: diesel

The same Tuesday, Trump said he favoured restricting US diesel exports, officially to bring down pump prices in the United States. The US is the world's largest exporter of the fuel. The reaction was immediate and measurable: on Wednesday, the European diesel premium over Brent exceeded $95 a barrel, a record in Bloomberg data going back to 2011. On Thursday, European diesel was still getting more expensive faster than the American benchmark, on the mere risk of a ban.

It is worth being precise about what this means. An export ban is not a shot fired. It kills no one, triggers no Article 5, needs no vote in Congress and appears on no sanctions list. Yet it delivers to a partner a supply shock in the fuel that runs its lorries, its tractors and part of its heating. It is an instrument of pressure with the yield of a sanction and the political cost of a statement.

Why Europe is a target

The question is not whether energy can be used as leverage — it always could. It is why now, and against whom. And the list of transatlantic grievances lengthened all at once in September.

Add it up: a Europe tying itself commercially to a country Washington sanctions, a Europe distancing itself diplomatically over Israel, a Europe that is at the same time discussing corridors with China. Each of these files has its own timetable. But they all share the same pressure point: Europe imports its energy, and from fewer and fewer places.

And the other target is Beijing

Around a fifth of the world's oil passes through the Strait of Hormuz, which Tehran has closed. Most of that crude goes to Asia, China first among buyers — it is also the leading buyer of Iranian crude. A blocked strait is not something to be argued at the WTO: it is a price rise that hits the world's workshop first, without a single tariff having been signed.

Beijing has understood this and is routing around it. The first Wuhan–Baku freight train left this year via the "Middle Corridor", the Eurasian axis that avoids both Russia and the straits. Meanwhile, Brussels has given Beijing until October to deliver "concrete results" on its trade surplus, failing which "harsher measures" will follow. Three blocs are therefore contesting the same corridor, in both directions.

The scenario: why this can last

An air and naval war can be suspended overnight: all it takes is an order to stop the sorties. A ground war cannot — it leaves positions to hold, convoys to protect, dead to avenge. If ground operations are added to the strikes, the risk premium stops being a bet on a communiqué and becomes a structural feature of the market. That is the difference between a barrel that can lose $20 in a session and a barrel that no longer does.

The real-world test came on Friday 25 September: on mere press reports of a phased agreement on Hormuz, Brent fell 2.1% in the session, yet still ended the week up 1.3%. In other words, the premium is intact and the market still regards it as temporary. That is precisely what makes it fragile in both directions.

The Caspian thesis: the two wars touch

The facts first. The Caspian Sea has become a logistics corridor between Iran and Russia. On 25 July 2026, a Ukrainian strike hit the Iranian cargo ship Ana near Astrakhan: one sailor killed, three wounded. Tehran promised reprisals without specifying a target. Kyiv let it be known that it was targeting Iranian military freight bound for Russia; several sanctioned vessels, including the Port Olya 2, had already been hit earlier in the year, as had a Russian warship in February.

Then the reasoning. Iran cannot strike Ukraine directly without crossing Russian or Turkish airspace. However, the depots that feed the Ukrainian effort — drones, munitions, parts — sit in neighbouring countries. An Iranian reprisal aimed at one of those warehouses would change the nature of the conflict: it would turn logistical support into de facto co-belligerence, and would hand Kyiv, which is struggling at the front, exactly what it lacks — allies drawn in by an act committed against them.

This is the point to retain, and it holds regardless of the probability of the chain: two theatres that share a supply route also share their escalations. A missed shot in the Caspian does not stay in the Caspian. As long as Iran ships across that sea and Ukraine strikes what sails on it, the risk of a junction is not zero — and it is in the price of no asset today.

What to watch

1. Whether the NPT withdrawal bill reaches the floor. Tabled on 20 September with triple urgency, it awaits the Iranian Parliament speaker's approval. A vote changes the nature of the nuclear file.
2. Follow-through on the diesel threat. A statement is already in the prices; a decree would be a different matter. Watch the diesel/Brent premium rather than Brent alone.
3. Indirect channels of discussion. Benjamin Netanyahu's visit to Abu Dhabi on 27 September, reported by an Israeli official, indicates that the Gulf circuits are still working.
4. The Caspian. Any strike on a sanctioned vessel, any Iranian reprisal outside the Middle Eastern theatre.
5. 3 November. If the timetable announced at the UN holds, the negotiating window opens afterwards — not before.

What this implies, soberly

An investor does not need to choose between these scenarios. They need to know which one is in the price. Today: the market prices a negotiated exit, while keeping the premium just in case. You can read it in the fact that a single press article is enough to move the barrel by 2%. What is expensive is not crude — it is refined product, and European distillate in particular, whose premium is at a fifteen-year record.

Nothing above is investment advice; we are not financial advisers. It is a framework for reading events, with its sources and its labels, to be tested against your own constraints.

Sources

• Bloomberg — export ban threat sends European diesel soaring
• Bloomberg — European diesel races ahead of US
• Al Jazeera — what a US export ban would do
• Rigzone — follow-up and market context
• Enerzine — fuel prices as of 25 September 2026 (in French)
• L'Énergeek — record diesel price on 18 September (in French)
• EnergyNow — weekly crude close, 25 September
• Al Jazeera — escalation in the Strait of Hormuz
• CNBC — "hostile act": Trump threatens EU with tariffs
• Axios — EU floats associate-member status for Canada
• Euronews — Brussels's October deadline for Beijing
• Tasnim — NPT withdrawal bill tabled, 20 September
• The Jerusalem Post — Netanyahu's trip to Abu Dhabi
• Al Jazeera — Iran accuses Ukraine after Caspian strike
• CNN — the Iran and Ukraine wars collide on the Caspian
• The Kyiv Independent — the Ukrainian version: a military cargo ship