Iran Forces Ships Into Hormuz Lanes

Hormuz is open, but only in the narrowest sense. Ships can still pass through the strait, but Iran wants that passage to happen on Tehran's terms. In late June, Iran's Revolutionary Guards told shipowners that only routes designated by Tehran would be allowed, warning of a "severe response" against vessels that refuse (CNBC).

The numbers explain why this matters even from Malta, where the impact would be felt through prices rather than empty fuel terminals. The strait carries roughly 20 million barrels of crude per day and about a fifth of global LNG trade (EIA). For Europe, the immediate test is not whether Iran formally closes Hormuz. It is whether insurers and shipowners start treating Tehran's preferred route as the only commercially usable one before governments have decided how to respond.

Two Lanes, One Threat

After the US and Iran agreed an interim reopening framework on June 17, Oman offered a toll-free corridor along its own coast, coordinated with the IMO, the UN body that sets global shipping-safety rules (Gulf Industry/ONA). Ships used it. On June 24, 78 vessels crossed the strait, with 42% taking the Omani route (S&P Global).

The next day, the IRGC rejected any non-Iranian lane. That turned a maritime workaround into a political confrontation.

Under UNCLOS, the UN law of the sea, coastal states cannot suspend "transit passage" through straits used for international navigation (UNCLOS). Iran is pushing beyond a normal security claim. Tehran is asserting the right to decide which route counts as legitimate, and to threaten ships that choose another.

Who Actually Decides a Voyage

Governments defend principles. Captains, insurers and charterers decide whether a voyage happens. A ship approaching Hormuz today will look at war-risk insurance, P&I club guidance, sanctions advice and charterparty clauses before the weather report. P&I clubs, the mutual insurers that cover shipping liability, have said cover is unavailable for trade that breaches sanctions (Shipowners' Club). BIMCO's standard war-risk clauses allow owners to refuse any transit they judge unsafe (BIMCO). Insurers say they may need months of stability before premiums come down (CNBC).

That leaves shipowners in a bind. Taking Tehran's approved lane can raise sanctions exposure. Avoiding it can mean physical danger and insurance that becomes too expensive to make the voyage worth doing.

Iran does not need to blockade the strait in the old sense. If private gatekeepers close off the alternatives through pricing, exclusions and risk clauses, Tehran gets much of the same leverage without declaring a closure.

What Europe Can and Cannot Do

The EU has moved, but with instruments designed for another kind of pressure. On June 8, the Council, where member-state governments take joint decisions, imposed sanctions against an IRGC Navy unit and two individuals under a newly extended framework. It was the first time the EU used sanctions specifically to defend freedom of navigation (2eu.brussels, Firstpost). France has insisted on unconditional free navigation and describes any military response in terms of demining and escort (La Gazette France).

Sanctions freeze assets and restrict travel. They do not clear mines, escort tankers or make a dangerous route insurable. That distinction matters for Malta as much as for Rotterdam or Piraeus, because a maritime economy lives off the difference between a legal right and a voyage that underwriters will actually cover.

Europe's naval presence shows the same gap. EMASOH/Agenor, the French-led European surveillance operation with about eight member states contributing, monitors the strait but has no enforcement mandate (EMASOH). Operation ASPIDES, launched in 2024 to protect Red Sea shipping, can escort vessels through danger zones, but it was built to deter Houthi attacks, not to force a coastal state to accept alternative corridors (Council of the EU).

Europe's energy exposure to Hormuz runs mainly through prices, not pipelines. Most crude passing through the strait goes to Asia, so the European hit would come through higher global oil prices, dearer freight and pressure on sectors that depend on fuel costs. The European Commission has pointed to aviation fuel as one area where the squeeze could bite hardest (EIA, Infobae/EFE).

The 60-day US sanctions licence holding up the current truce expires on August 21. If ships keep using Oman's corridor and underwriters begin quoting workable prices for it, Iran's grip weakens. If mines and attacks leave only the Iranian route safe enough to insure, transit passage — the rule that no coastal state can block an international strait — begins to depend on the permission of the actor threatening it. That would be a precedent far beyond the Gulf.