Iran's Islamic Revolutionary Guard Corps (IRGC) Navy announced the complete closure of the Strait of Hormuz on Saturday night, May 4, 2026 [1, 2].
Because the strait is a primary artery for global energy, any disruption threatens the stability of international oil markets and increases the risk of direct military conflict between Iran and the U.S.
The IRGC Navy said that any vessel moving in the area would be targeted [1, 3]. This action comes in response to what Tehran describes as a continuing U.S. naval blockade and the disabling of an Iranian oil tanker in the Gulf of Oman [1, 3].
An IRGC Navy spokesperson said, "No vessel should make any movement from its anchorage in the Persian Gulf and the Strait of Hormuz" [1]. The military has shifted the status of the waterway back to "strict control" [2].
The Strait of Hormuz links the Persian Gulf with the Gulf of Oman [1, 5]. In peacetime, approximately 20% of the world's oil and natural gas is shipped through this passage [5].
An IRGC official said, "Any disruption will face a decisive response" [4]. While some reports indicate a total closure until the U.S. blockade is lifted, other accounts suggest Iran may ensure passage once the U.S. pauses its operations [1].
Some observers noted that the strait was already under strict control prior to the new announcement [5]. However, the IRGC has framed this latest move as a complete closure of the waterway [1].
“"No vessel should make any movement from its anchorage in the Persian Gulf and the Strait of Hormuz."”
The closure of the Strait of Hormuz represents a significant escalation in regional tensions. By threatening to target all vessels, Iran is leveraging its geographic control over a critical chokepoint to pressure the U.S. into ending its naval operations. This move could trigger a global energy price spike and force international shipping companies to seek costly alternatives or request naval escorts.
