Iran has escalated its strategic assertiveness in the Strait of Hormuz, issuing a new maritime directive that threatens British commercial shipping. The move, announced by the Islamic Revolutionary Guard Corps, extends Tehran's declared maritime control zone and warns against what it terms "unauthorised passage" by vessels flagged to the United Kingdom.
The strait, a chokepoint for roughly one-fifth of global oil supply, has long been a flashpoint in Gulf security. Iran's latest action builds on years of calibrated provocations, including the 2019 seizure of the British-flagged tanker Stena Impero and subsequent harassment of commercial traffic. The new claim appears designed to test the resolve of London and its allies ahead of expected diplomatic negotiations over a broader nuclear deal.
Whitehall sources described the measure as "unacceptable" and confirmed that the Royal Navy has increased its escort rotations for UK-linked vessels in the region. The Ministry of Defence has not disclosed specific operational details but stated that HMS Montrose and HMS Defender remain on station to uphold freedom of navigation.
The move coincides with heightened rhetoric from Supreme Leader Ali Khamenei, who last week restated Iran's right to close the strait in response to Western sanctions. Analysts suggest the directive is calibrated to maximise leverage without triggering a direct military confrontation.
The United States Fifth Fleet, based in Bahrain, condemned the declaration as a violation of international law. A spokesman said it would continue to patrol alongside allied forces to ensure the strait remains open. The British government has not yet announced formal diplomatic measures, but officials indicated that the issue will be raised at the next session of the UN Security Council.
For British shipping firms, the immediate impact has been a rise in insurance premiums and delay in transit schedules. Several operators have opted for alternative routes around Africa's Cape of Good Hope, adding weeks to journey times and increasing costs. The London insurance market warned that premiums for war risk cover in the region have tripled.
The development underscores the fragile equilibrium in the Gulf, where soft power and strategic posturing often precede economic coercion. Tehran's long-term objective, analysts argue, is to fragment the coalition of nations that uphold maritime security while advancing its own economic and diplomatic interests through controlled escalation. For London, the challenge lies in deterring further Iranian actions without triggering a broader crisis that could engulf the region.
