U.S. Blockade on Ships Entering or Exiting Iranian Ports
Issued: 3 months, 1 week ago
Date Reference Region Category Aggressors Source
2026-04-13 14:00:00 CW Alert 006- (Apr 26) Indian Ocean Advisory Military Open source/UKMTO
Open-source have reported that U.S. Central Command forces will implement a blockade of all maritime traffic entering and exiting Iranian ports, effective 13 April 2026 at 1400 UTC. The blockade will be enforced impartially against vessels of all nations entering or departing Iranian ports and coastal areas, including all Iranian ports on the Arabian Gulf and Gulf of Oman. CENTCOM forces have stated they will not impede freedom of navigation for vessels transiting the Strait of Hormuz to and from non-Iranian ports. All mariners are advised to monitor Notice to Mariners broadcasts and contact U.S. naval forces on bridge-to-bridge channel 16 when operating in the Gulf of Oman and Strait of Hormuz approaches. UPDATE 1: The UKMTO have confirmed that neutral vessels currently within Iranian ports have been granted a limited grace period to depart. UPDATE 2: A further update from JMIC has reported that in addition to enforcing the blockade, all Iranian vessels, vessels with active OFAC sanctions, and vessels suspected of carrying contraband, are subject to belligerent right to visit and search. These vessels, regardless of location, are subject to visit, board, search, and seizure. UPDATE 3: The JMIC have issued further information informing that ships aiding vessels violating the blockade by conducting ship-to-ship transfers with them are also in violation of the blockade. UPDATE 4: The JMIC have released a further update stating that the blockade of Iranian ports remains in effect pending the execution of the US-Iran ceasefire agreement scheduled for 19 June 2026. Vessels subject to blockade enforcement should continue compliance with direction from blockading forces. Failure to immediately comply may result in rapid escalation to disabling or destructive fire. Masters are advised to take special caution not to endanger their crews during blockade enforcement actions by failing to abide by instructions specifically given to ensure their safety and security.
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