Iran shifts to long-term control of Hormuz Strait

IRAN

Attacks and restrictions point to a strategy of keeping the Strait open but unstable, maintaining pressure on global trade even after hostilities end

IRAN is likely to retain effective control of the Strait of Hormuz even after hostilities end, reopening the route before restricting it and attacking vessels within hours.

Over the past 72 hours, it has reopened the route, then restricted it, attacked vessels and closed it again, in a pattern that reflects competing pressures within Iran, where the IRGC’s naval arm appears to favour a harder line.

Tehran’s announcement that the Strait would be “completely open” for the duration of the ceasefire was quickly overtaken by events on the water.

Within hours, Iranian forces had engaged vessels near the shipping lane, with gunboats firing on a tanker and a separate strike damaging a container ship.

The incidents caused limited damage and no reported casualties, but underline how quickly access to the Strait can be tightened.

Rather than attempting a full blockade – a move that would risk immediate escalation with the United States and its allies – Tehran is operating below that threshold.

Traffic continues, but under conditions shaped by uncertainty, legal risk and the visible possibility of intervention.

That approach is already affecting behaviour. Commercial transit is unlikely to return to pre-conflict levels in the near term, despite the formal reopening of the route.

Shipping companies remain wary of the legal, financial and physical risks associated with transit, including potential sanctions exposure, insurance constraints and the possibility of vessels being intercepted or caught in any renewed escalation.

Even where access is technically permitted, the environment remains tightly controlled. “Iran never suggested this would be completely hands-off,” says Benedict Manzin, Lead Middle East & Africa Analyst at Sibylline.

“They made clear vessels would have to follow a co-ordinated route – they are still dictating how passage through the Strait works.”

Operational limits reinforce that caution. Ships are being directed along designated corridors through relatively narrow channels, constraining the volume of traffic and increasing the risk of congestion.

Larger vessels, particularly those operating at slower speeds, are likely to remain reluctant to transit while the ceasefire remains fragile.

The result is a form of managed instability. The Strait is neither closed nor fully open, but functioning under sustained pressure. Even limited interference is sufficient to deter some operators and drive others to reroute via longer alternatives, including around the Cape of Good Hope.

That extends transit times, increases fuel costs and maintains pressure on global supply chains.

“Elevated attack risks against vessels will persist,” Manzin says, reflecting the continued volatility in the waterway.

The disruption is already spreading beyond maritime trade.

More than a dozen countries have indicated they would be willing to join a future mission to protect shipping in the Strait once conditions allow, while European leaders have called for the restoration of free passage.

For now, such plans remain contingent on a durable ceasefire and would likely require coordination with both Washington and Tehran.

And with neither Iran nor the United States a signatory to the UN Convention on the Law of the Sea, enforcement of navigation rights in the Strait remains dependent less on treaty obligations than on military and political leverage.

Continued uncertainty around energy flows has raised concerns over potential jet fuel shortages in Europe, with airlines cutting capacity and preparing for further volatility.

Longer shipping routes, higher insurance costs and extended crew commitments are already feeding into broader inflationary pressures.

The effort also highlights the limits of international legal frameworks.

At the same time, diplomatic engagement continues.

Washington and Tehran have signalled openness to further talks, with both sides appearing to favour an interim arrangement rather than a comprehensive settlement.

Despite recent incidents, the likelihood of an immediate breakdown in negotiations remains limited, even as tensions remain elevated.

Iran has since reclosed the Strait, saying it will remain shut until the United States lifts its blockade of Iranian ports, reinforcing the link between access and the wider standoff.

That balance allows both sides to pursue negotiations while maintaining pressure on the ground. Iran is able to disrupt shipping without triggering full escalation, while the continued US naval presence sustains a high-risk operating environment.

Military activity on both sides remains in close proximity, increasing the likelihood of miscalculation even as talks proceed.

Taken together, these dynamics point towards a longer-term pattern in which the Strait remains operational but persistently unstable. A full return to pre-conflict norms appears unlikely in the near term, but so too does a sustained closure.

Instead, the most likely outcome is continued intermittent interference, elevated risk and constrained but ongoing transit.

This risks transforming the Strait from a secure trade corridor to a pressure point, with access increasingly conditional on the balance of forces in the region.

Manzin adds: “It is effectively a case of if you are going to keep blocking my ships, then I’ll block yours.”

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