Iranian sea trade blocked as six ships forced to turn back, US military says

Admiral Brad Cooper said an estimated 90% of Iran’s economy is fuelled by international sea trade. Photo / Nicolas Economou, NurPhoto, AFP

A US blockade has “completely halted economic trade” to and from Iranian ports by sea, the US military said, hours after military officials said US warships confronted six merchant vessels departing an Iranian port and forced them to turn back.

The US blockade, which took effect on Monday amid a shaky ceasefire between the United States and Iran, involves 10,000 American troops, more than a dozen Navy ships positioned in the Gulf of Oman and the Arabian Sea, and an array of fighter jets and drones to surveil commercial vessels in the area, US Central Command said in a post on social media.

Admiral Brad Cooper said late on Tuesday that an estimated 90% of Iran’s economy is fuelled by international sea trade.

“In less than 36 hours since the blockade was implemented, US forces have completely halted economic trade going into and out of Iran by sea,” the Centcom commander said in a separate post.

Before the US and Israel began the war against Iran, and Tehran closed the Strait of Hormuz in retaliation, about 20% of global oil supply – roughly 20 million barrels of oil – and 20% of the world’s liquefied natural gas trade passed through the strait daily. A global spike in gas prices has increased pressure on the Trump administration to find a resolution to the conflict, but negotiations over the weekend in Pakistan concluded without an agreement.

On Tuesday, China, a major buyer of Iranian oil that has sought to distance itself from direct involvement in the war, criticised the US blockade as a “dangerous and irresponsible move”.

“This will only aggravate confrontation, escalate tension, undermine the already fragile ceasefire and further jeopardise safe passage through the Strait of Hormuz,” Foreign Ministry spokesperson Guo Jiakun said.

To execute the blockade, two US officials said, American naval assets are not lingering near Iranian ports or in the Strait of Hormuz itself. Iranian forces mined the strait, one of several flashpoints in negotiations, soon after hostilities began more than six weeks ago. The narrow, shallow corridor also leaves any vessels there vulnerable to attack.

The officials spoke on the condition of anonymity to disclose details about the operation that have not been made public.

“Our net is the Gulf of Oman,” said one of the officials, who explained that the US warships involved wait for an opportune moment – after observing vessels leave Iranian facilities and clear the strait – before intercepting the merchant ships and forcing them to turn around.

“There’s one way in and one way out,” the official said. “We’ve got the whole thing on lockdown.”

None of the six encounters required escalation by US forces to compel the ships to turn around, both officials said.

The blockade affects only those ships that were either still in an Iranian port, or pulled into one, after 10am Eastern time Monday (2am April 14 NZT), one of the officials said.

Iranian Press TV reported earlier on Tuesday that two ships that had been in Iranian ports had passed through the blockade – but in both cases, the ships had departed before the US-imposed deadline, according to ship tracking data cited by the network.

US warships are not escorting the intercepted vessels back to the Iranian ports, both officials said. However, US forces “are supporting freedom of navigation for vessels transiting the Strait of Hormuz to and from non-Iranian ports”, Centcom said in its statement.

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