Tehran, 18 April 2026 — Iran has formally closed the Strait of Hormuz effective Saturday evening, the Islamic Revolutionary Guard Corps (IRGC) Navy Command announced, declaring the closure will remain in force until Washington unconditionally lifts its naval blockade of Iranian ports. The announcement, broadcast by Iran’s state-run IRIB network, marks one of the most consequential escalations in the Persian Gulf in recent memory, with immediate implications for global energy markets.
“As a result of the violation of the ceasefire regime, the Strait of Hormuz will be closed from the evening of today [Saturday], until the US lifts the naval blockade,” the IRGC Navy stated in its official communiqué. The command further issued an unambiguous warning that any vessel attempting to approach the waterway would be subject to military strikes, characterising such transit as “cooperation with the enemy” — a direct reference to the United States.
The closure follows a naval blockade imposed by the US Navy on 13 April, which has effectively sealed all maritime traffic entering and exiting Iranian ports on both sides of the Strait of Hormuz. The strategic waterway is of extraordinary global significance, serving as the transit corridor for approximately 20 per cent of the world’s oil, petroleum products, and liquefied natural gas supplies. Any sustained disruption to navigation through the Strait is expected to send immediate shockwaves through international energy markets and global shipping lanes.
Washington has maintained that non-Iranian vessels retain the right to transit the Strait of Hormuz freely, provided they do not remit toll payments to Tehran. Iranian authorities have not formally announced the imposition of such a toll, though discussions regarding the measure have been reported at the governmental level. The IRGC’s invocation of a “ceasefire regime violation” as the legal and political basis for the closure suggests Tehran views the US naval blockade as a direct breach of prior diplomatic understandings, further complicating the already fraught bilateral relationship.
The closure of the Strait of Hormuz, if sustained, would represent an unprecedented disruption to the global energy supply chain, affecting not only Western economies but also major importers across Asia, including China, India, Japan, and South Korea. Analysts across the Global South have long warned that the unilateral application of US naval power in international waterways constitutes a direct threat to the sovereign rights of littoral states and the principle of freedom of navigation as enshrined in international maritime law.
Iran’s Vice President also separately stated on Saturday that control of the Strait of Hormuz “will be secured one way or another,” signalling that Tehran views the matter as a non-negotiable question of national sovereignty and strategic deterrence.
Find more details at Sputnik International.