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.
Other alerts for

Indian Ocean


Fire on board an LPG Tanker in the Gulf of Aden

The UKMTO have been informed by the Company Security Officer that a vessel has been struck by an unknown projectile whilst underway, approximately 109nm Southeast …

Electronic Interference in the UKMTO

The UKMTO have reported an increase of GNSS interference, including "AIS speed anomalies" from vessels operating in the UKMTO Voluntary Reporting Area between the 3rd …

Aerial Attack on a cargo vessel, Gulf of Aden

The UKMTO have received a report from the Master of a vessel, stating that a splash and smoke was witnessed astern of the vessel, whilst …

Aerial attack on a cargo vessel, Gulf of Aden

The UKMTO have received a report from the Master of a vessel, stating that a splash and explosion occurred in close proximity to the vessel, …

UKMTO Advisory - Extreme caution recommended in the vicinity of ports already subjected to strikes, Yemen

The UKMTO have issued an advisory stating that even though there appears to be a reduction in reported threat levels within the wider Gulf region …

Israeli Air Strikes on Hodeidah Port, Yemen

Open-source media has reported that following evacuation orders given by the Israeli Military, Israel conducted twelve air strikes on the Port of Hodeidah, Yemen (exact …

Missile sighting reported, Red Sea

The Master of a Marshall Islands-flagged bulk carrier has reported sighting a missile whilst underway approximately 89nm West-southwest of Jizan, Saudi Arabia. The Master reported …

Aerial attack on a Tanker, Red Sea

The UKMTO have reported that a vessel was attacked approximately 40nm Southwest of Yanbu, Saudi Arabia. The Master reported a splash in the ocean in …

Suspicious Activity Towards a Livestock Carrier, Red Sea

It has been reported that a Comoros-flagged livestock carrier has been subject to an approach whilst underway, approximately 30nm Northwest of Mocha, Yemen. A single …