Hormuz closure threat jolts Gulf shipping

The Persian Gulf Strait Authority has said the Strait of Hormuz will be “completely closed” to transit traffic, escalating fears of a wider maritime disruption at the world’s most sensitive energy chokepoint as tensions involving US military operations intensify.

The notice, issued through a post on X, cited “aggressive US forces” and an announcement by the IR Armed Forces as grounds for the planned closure. It told companies and vessel operators that had already obtained transit permits to remain patient and wait for further instructions, signalling that existing approvals may no longer guarantee passage through the narrow waterway linking the Persian Gulf with the Gulf of Oman.

The claim immediately drew scrutiny because the Strait of Hormuz is not governed by a single internationally recognised authority with unilateral power to halt all commercial navigation. Maritime movement through the channel is shaped by coastal state control, naval presence, shipping insurance, vessel tracking, port instructions and security advisories. A complete shutdown would require enforcement at sea, not merely a digital notice, and ship operators are expected to rely on warnings from flag states, naval coalitions, insurers and port agents before rerouting vessels or suspending sailings.

The strait handles a large share of seaborne crude and liquefied natural gas exports from Gulf producers, making any closure threat capable of triggering sharp market reaction. Tankers carrying crude from Saudi Arabia, the UAE, Kuwait, Iraq and Qatar pass through the waterway, while Qatar’s LNG trade is particularly exposed because nearly all its seaborne gas shipments move through the same corridor. Even a partial halt can raise freight rates, war-risk premiums and delivery delays across Asia and Europe.

Shipping executives have been watching the area closely after a series of military warnings, drone incidents and competing claims over vessel safety. US Central Command has said commercial ships continue to move through the strait despite threats, while Tehran-linked military statements have presented Iran as capable of controlling passage. The gap between those positions has left vessel operators facing a familiar problem: the legal status of the route may remain open, but the commercial risk can become too high for insurers and charterers.

Energy markets are likely to treat the PGSA post as a risk signal rather than proof of a physical blockade unless vessel-tracking data show a sustained fall in traffic. Traders typically look for changes in tanker speed, AIS transponder behaviour, anchorage build-ups near Fujairah and the Gulf of Oman, and notices from marine insurers. A sudden increase in ships waiting outside the strait would suggest operators are pausing movements while they assess the threat.

The announcement also lands at a delicate point in US-Iran tensions. Military activity around the Gulf has already raised the prospect of miscalculation, particularly if naval units, drones and commercial tankers operate in close proximity. Any attempt to enforce a closure could draw direct confrontation with US and allied naval assets, while an ambiguous warning could still disrupt commerce by making insurers unwilling to cover voyages.

For Gulf exporters, the strategic vulnerability is well known. Saudi Arabia and the UAE have pipeline routes that can move part of their crude exports outside Hormuz, but those systems cannot fully replace seaborne flows through the strait. Iraq and Kuwait remain heavily dependent on the route. Qatar has no comparable alternative for LNG exports at scale, making gas markets especially sensitive to any prolonged disruption.

The legal picture is contested. International shipping relies on the principle of transit passage through straits used for global navigation, but Iran has long argued that hostile military activity in the Gulf gives it security grounds to impose restrictions. The United States rejects any unilateral closure and has maintained that freedom of navigation must be protected. That clash of interpretations has repeatedly turned Hormuz into both a military flashpoint and a diplomatic bargaining chip.