Shipping traffic through the Strait of Hormuz remained mostly at a standstill on Monday, with just three vessels crossing the vital waterway, according to Kpler, a maritime data firm.
On Sunday, a US Navy destroyer attacked and seized an Iranian-flagged cargo ship that US President Donald Trump said had tried to evade the US blockade on ships traveling to and from Iranian ports.
In a separate incident, the United Kingdom Maritime Trade Operations center, which is administered by Britain’s Royal Navy, said that two vessels had been hit while trying to cross the Strait of Hormuz, according to a notice published on Saturday.
In one instance, gun ships operated by Iran’s Revolutionary Guards Corps fired at a tanker without radio warning, the British organization said. In the second incident, a container ship was hit by “an unknown projectile” that damaged some of the containers.
On Tuesday, the US military said it had seized an Iran-linked tanker in international waters, in what appears to be the latest move to enforce a blockade as the ceasefire deadline looms.
The US military said it had boarded the tanker Tifani “without incident.”
The ship, capable of carrying 2 million barrels of crude, last reported its position on Tuesday morning near Sri Lanka in the Indian Ocean, according to MarineTraffic tracking data. It was close to fully loaded and had signaled Singapore as its destination.
A two-week ceasefire between the US and Iran is set to expire early Wednesday.
Latest developments
The US Navy has turned back 27 ships trying to enter or exit Iranian ports since an American blockade outside the contested Strait of Hormuz began about a week ago, the military’s Central Command said on Monday.
On Sunday, a Navy destroyer disabled and seized the Touska, an Iranian cargo ship, in the Gulf of Oman after it tried to evade the blockade. It was the first time a vessel was reported to have tried to evade the US-imposed blockade on any ship entering or exiting Iranian ports since it took effect last week.
The guided-missile destroyer Spruance, one of more than a dozen Navy warships enforcing the US blockade, ordered the vessel’s crew to evacuate its engine room.
The Spruance then fired several rounds from its Mk-45 gun into the ship’s propulsion system as it steamed toward the port of Bandar Abbas in Iran, Central Command said in a statement that included a video of the firing.
American officials will determine what to do with the disabled vessel once the search is completed, a US military official said on Monday, speaking on the condition of anonymity to discuss operational matters, according to the New York Times. One option would be to tow the stricken ship to Oman, independent specialists said. An alternative would be to let the Touska steam to an Iranian port, if it can.
A spokesman for Iran’s military reiterated a threat on Monday to “take the necessary action against the US military” in response to the ship’s seizure, Iran’s state broadcaster reported.
How is the US imposing the blockade?
According to CENTCOM, more than 10,000 US personnel, including sailors, marines, and airmen, are participating in the operation, supported by over a dozen warships and dozens of aircraft. The effort spans key waterways surrounding Iran, including the Arabian Gulf and the Gulf of Oman.
The US blockade on Iranian ports does not have a defined geographic boundary, and the United States can interdict vessels almost anywhere in international waters until they arrive at their final port.
Analysts say modern technology allows blockade enforcement at great distances.
Can ships evade the blockade?
Maritime intelligence experts say that more ships in and around the Strait of Hormuz seem to be adopting “spoofing” tactics to avoid detection.
Under international maritime law, most large commercial vessels travel with a transponder that automatically transmits the ship’s name, location, route and other identifying information. That includes a nine-digit number with a country code, which serves as a digital fingerprint for a ship.
The tactics were used by Russian “shadow fleet” vessels evading sanctions related to the invasion of Ukraine in 2022.
When a ship is engaged in spoofing, its captain can type in a false origin or destination or can pretend to be piloting another ship altogether. Vessels can also temporarily turn off their transponders, seeming to disappear in one place and reappear in another.
The strait is “a contested information environment,” said Erik Bethel, a partner at Mare Liberum, a maritime technology venture capital fund.
Still, whatever ruses they employ, vessels going to and from Iran may get only so far. It is difficult to pass between the open ocean and a waterway as narrow as the Strait of Hormuz without being detected.
“My expectation is that the US Navy can sit out in the Gulf of Oman,” said Ami Daniel, the chief executive of Windward, a maritime intelligence data provider. “I don’t think there’s a way to breach the blockade.”
What are the US and Iranian strategies?
The US blockade sets up a significant test in the Iran war: Which side can endure more economic pain?
Instead of directing missiles and bombs, Trump is trying to choke off Iran’s oil exports, which make up just about all of the government’s revenue.
Some experts questioned whether the US blockade would work.
“Iran is already hurting, and they have shown that they are willing to take more than a couple of hits,” said Ahmet Kasim Han, a professor of international relations at TED University in Ankara, Türkiye.
Iran’s strategy appears to be using its leverage over global energy markets, where Tehran has discovered new powers that can cause pain in the US economy through spikes in the price of gasoline and other staples.
Why is the strait so important?
The Strait of Hormuz is a strategic waterway connecting the Gulf to the Gulf of Oman and the Indian Ocean. It is the only sea route for moving oil, natural gas and other cargo out of the Gulf. Iran’s coastline runs along the entire route.
At the strait’s narrowest and most vulnerable point — between Iran to the north and the Musandam Peninsula of Oman to the south — the navigable channel is about two miles wide each for inbound and outbound traffic, according to the International Energy Agency.
The legal status of the strait is complex. It lies within the territorial waters of Iran and Oman, but under international law it is treated as an international waterway where ships are generally guaranteed passage.
Iran has signed but not ratified that framework and has disputed the extent of those rights.
Before the war, about 20% of global oil and liquid natural gas passed through the strait. Most of the fossil fuels are bound for Asia, especially China, India, Japan and South Korea.
Other large vessels also use the strait, including car carriers and container ships.
Crucial industrial goods traveling through Hormuz include helium from Qatar, fertilizer from Oman and Saudi Arabia, and plastic feedstocks from Saudi Arabia and Emirati petrochemical plants.
How does Iran control the strait?
Iran’s military can threaten shipping traffic throughout the Strait of Hormuz, even though much of its navy has been destroyed by US and Israeli strikes.
The United States and Israel launched their war against Iran on the argument that if Iran one day got a nuclear weapon, it would have the ultimate deterrent against future attacks.
It turns out that Iran already has a deterrent: geography.
“The Iranians have thought a lot about how to utilize the geography to their benefit,” said Caitlin Talmadge, a professor at the Massachusetts Institute of Technology who studies Gulf security.
*The New York Times
