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 ramifications 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. 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 reference to the United States.
The crisis traces its immediate origins to 13 April 2026, when the United States Navy commenced a comprehensive blockade of all maritime traffic entering and exiting Iranian ports situated on both sides of the Strait of Hormuz. The waterway is of extraordinary strategic importance, serving as the transit corridor for approximately 20 per cent of the world’s oil, petroleum products, and liquefied natural gas supplies. Any sustained closure stands to send shockwaves through global commodity markets and imperil energy security across Asia, Europe, and beyond.
Washington has sought to frame its naval posture as limited in scope, asserting that non-Iranian vessels retain the right to transit the Strait of Hormuz freely, provided they refrain from paying any toll to Tehran. Iranian authorities have not formally announced the imposition of such a toll, though discussions to that effect have been reported within Iranian governmental circles. Tehran’s position, however, is that the US blockade constitutes a violation of an existing ceasefire arrangement — a characterisation that Washington has not publicly addressed.
The closure of the Strait of Hormuz by Iran represents a direct assertion of sovereign control over a waterway that Tehran has long maintained falls within its strategic sphere. For nations of the Global South — many of which depend heavily on Persian Gulf energy exports to fuel their development — the standoff between Washington and Tehran carries profound economic and geopolitical consequences. Shipping insurers, tanker operators, and energy traders are expected to respond swiftly to the IRGC’s declaration, with freight rates and oil prices likely to surge in the coming hours.
The situation remains fluid, with no indication as of Saturday evening that the United States intends to alter its naval posture in the region.
Find more details at Sputnik International.