U.S. Turns Back Ten Ships as Iran Port Blockade Holds, Tankers Test Limits

The United States says its maritime blockade of Iranian ports is continuing to hold, with U.S. Central Command reporting that ten vessels have been turned back in the first 48 hours of enforcement and no ships have successfully entered or exited Iranian ports by sea.

In a statement, CENTCOM said the vessels “complied with direction from U.S. forces to turn around and return toward an Iranian port or coastal area,” building on earlier figures from the first day of the operation when six ships were ordered to reverse course.

“A blockade of Iranian ports has been fully implemented,” said Adm. Brad Cooper, the command’s top officer. “In less than 36 hours since the blockade was implemented, U.S. forces have completely halted economic trade going into and out of Iran by sea.”

U.S. naval messages to vessels in the region have warned that ships attempting to call at Iranian ports could be boarded, diverted, or seized. Mariners have been told to abandon voyages to Iran and “not attempt to breach the blockade,” with the Navy stating that force could be used if vessels do not comply.

U.S. naval vessels are on patrol in the Gulf of Oman as CENTCOM continues to execute a U.S. blockade on ships entering and departing Iranian ports. U.S. forces are present, vigilant, and ready to ensure compliance. pic.twitter.com/dnHR2oz0ZN

— U.S. Central Command (@CENTCOM) April 15, 2026

U.S. officials have also provided details of early enforcement actions. A Navy destroyer contacted two tankers leaving the Iranian port of Chabahar and ordered them to turn around, according to a U.S. official familiar with the operation. Both vessels complied.

On Wednesday, U.S. Central Command reported that the destroyer USS Spruance (DDG 111) redirected an Iranian-flagged cargo ship that had tried to evade the U.S. blockade after transiting Hormuz along Iran’s coastline from Bandar Abbas, Iran. “Ten vessels have now been turned around and ZERO ships have broken through since the start of the U.S. blockade on Monday,” CENTCOM said.

The blockade is being carried out by a large U.S. force, with more than 10,000 personnel, over a dozen warships, and dozens of aircraft deployed across the region, according to the military.

The measures target ships entering or leaving Iranian ports, while U.S. officials say traffic through the Strait of Hormuz to other destinations remains permitted. Even so, vessel movements in the area have slowed sharply as shipowners assess the risks.

Tracking data shows several ships have delayed or reversed course near the approaches to the strait in recent days.

The sanctioned tanker Rich Starry (IMO: 9773301) reversed course in the Gulf of Oman after traversing the Iranian-controlled route of Strait of Hormuz and is now anchored off Iran after failing to proceed. At the same time, two sanctioned VLCCs, Alicia (IMO: 9281695) and RHN (IMO 9208215), have entered the Persian Gulf empty and may load Iranian crude, according to tracking data shared by TankerTrackers.

One crude carrier has also made it through the strait under the new conditions. The Malta-flagged VLCC Agios Fanourios I (IMO: 9759824), tracked by MarineTraffic, entered the Persian Gulf after waiting offshore for nearly two days and is heading to Iraq. The vessel also used the Iranian-controlled route hugging Iran’s coastline.

“U.S. forces are supporting the freedom of navigation for vessels that are transiting the Strait to and from non-Iranian ports,” said U.S. Press Secretary Karoline Leavitt.

Analysts say it is too early to judge how effective the blockade will be over time. Some vessels involved in Iranian oil trades do not broadcast their positions, making movements difficult to track.

The blockade follows the collapse of talks between the United States and Iran. Donald Trump has said the goal is to force Iran to reopen the Strait of Hormuz and accept U.S. terms.

“China is very happy that I am permanently opening the Strait of Hormuz. I am doing it for them, also – And the World. This situation will never happen again. They have agreed not to send weapons to Iran,” Trump posted to Truth Social.

“President Xi will give me a big, fat, hug when I get there in a few weeks. We are working together smartly, and very well! Doesn’t that beat fighting??? BUT REMEMBER, we are very good at fighting, if we have to – far better than anyone else!!!,” Trump added.

Updated: May 27, 2026 (Originally published April 15, 2026)

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