US President Donald Trump said Monday that the American military had begun a blockade of Iranian ports as part of his effort to force Tehran to open the Strait of Hormuz and accept a deal to end the war that has raged for more than six weeks.
Iran responded with threats on all ports in the Persian Gulf and the Gulf of Oman, taking aim at US-allied countries.
That set the stage for an extraordinary showdown that posed serious risks for the global economy and raised the specter that the ceasefire could collapse and the war could resume. Talks aimed at permanently ending the conflict — which began Feb. 28 with US and Israeli strikes on Iran — failed to reach an agreement this past weekend. There has been no word on whether negotiations will resume.
“We can’t let a country blackmail or extort the world because that’s what they’re doing,” Trump said of Iran at the White House, where he announced the blockade had started.
He suggested the US remains willing to engage with Iran.
“I can tell you that we’ve been called by the other side,” Trump said, adding that “they want to work a deal.” He did not say who called or what was discussed.
A notice to mariners by the UK Maritime Trade Operations agency said the blockade restricted “the entirety of the Iranian coastline, including ports and energy infrastructure.”
It said transit through the strait “to or from non-Iranian destinations is not reported to be impeded,” though ships “may encounter military presence.”
At least two tankers approaching the strait Monday turned around soon after the US blockade began, vessel tracker MarineTraffic said in a post on X.
Iran’s effective closure of the strait, through which 20% of traded oil passes in peacetime, has sent oil prices skyrocketing, pushing up the cost of gasoline, food and other basic goods far beyond the Middle East.
Before the blockade, Tehran had allowed some ships perceived as friendly to pass while charging considerable fees, leading to accusations it is holding the global economy hostage.
Some analysts are doubtful that the United States can restore normal shipping through force alone. And it’s not clear how the blockade will work or what the dangers might be to US forces.
The question is essentially who can endure the most pain: Could a blockade make Iran’s economic situation untenable and force it to concede? Or will it drive global oil and other prices so high that Trump is forced to back down?
The US military’s Central Command announced the blockade would be enforced “against vessels of all nations entering or departing Iranian ports and coastal areas” on the Persian Gulf and Gulf of Oman.
CENTCOM’s decision to allow ships traveling between non-Iranian ports to transit the strait was a step down from Trump’s earlier threat to blockade the waterway.
In a social media message, Trump said Iran’s navy had been “completely obliterated” but still had “fast attack ships.” Trump warned that “if any of these ships come anywhere close to our BLOCKADE, they will be immediately ELIMINATED.”
Iran issued threats of its own.
“Security in the Persian Gulf and the Sea of Oman is either for everyone or for NO ONE,” the Islamic Republic of Iran Broadcasting reported Monday. “An Iranian military statement said: “NO PORT in the region will be safe.”
The threats halted the limited ship traffic that resumed in the strait since the ceasefire, according to a report from Lloyd’s List Intelligence. Marine trackers say over 40 commercial ships have crossed since the start of the ceasefire last week, down from 100 or more vessel passages per day before the war.
The blockade is intended to pressure Iran, which has exported millions of barrels of oil since the war began, much of it likely carried by so-called dark transits that evade Western sanctions and oversight.
But the effects will be felt far beyond Iran. The price of Brent crude oil, the international standard, hovered Monday just under $100 per barrel. It cost roughly $70 per barrel before the war.
British Prime Minister Keir Starmer and French President Emmanuel Macron said they plan a summit this week seeking to end the conflict and unblock the strait.
Top-ranking Iranian officials threatened retaliation.
Ebrahim Rezaei, a spokesperson for the Iranian parliament’s National Security Commission, dismissed US the threat of a US blockade as “more bluffing than reality.”
“It will make the current situation (Trump) is in more complicated and makes the market — which he is angry about — more turbulent,” he said in a post on X.
The Iranian parliament speaker, Mohammad Bagher Qalibaf, addressed Trump in a statement: “If you fight, we will fight.”
Meanwhile, Iran’s representative to the United Nations, Amir-Saeid Iravani, demanded compensation from five Middle Eastern countries that Iran says violated international law by aiding the war effort against it, the Islamic Republic’s state-run media said Monday.
Iran’s official news agency, IRNA, reported that Iravani said Bahrain, Saudi Arabia, Qatar, Jordan and the United Arab Emirates owe Iran for “material and moral damages.”
US military officials have offered few details about how the blockade will actually work.
The US Navy has 16 warships, including the aircraft carrier USS Abraham Lincoln, in the Middle East, a defense official said. A second defense official said no American warships are in the Persian Gulf, which forms most of Iran’s coastline. Both spoke on condition of anonymity to discuss sensitive military operations.
Under international law, the blockade must be impartially enforced. Legal experts will also be watching to see if the US allows humanitarian aid to reach Iran.
“How it is carried out will determine whether it is lawful or not,” said Todd Huntley, a retired Navy captain and director of Georgetown University’s national security law program.
The blockade threat came after marathon US-Iran ceasefire talks in Pakistan ended without an agreement on Saturday.
US Vice President JD Vance said the talks stalled after Iran refused to accept American terms on refraining from developing a nuclear weapon.
Iran has insisted its nuclear program is peaceful. However, it has pushed forward with steps that could give it the ability to build a nuclear weapon, including enriching uranium to near weapons-grade levels and developing long-range missiles potentially capable of delivering a bomb.
Iran’s ambassador to India, Mohammad Fathali, said the main sticking points for Tehran were its nuclear program, war reparations and sanctions relief.
Neither Iran nor the US has indicated what will happen after the ceasefire expires on April 22. The fighting has killed at least 3,000 people in Iran, 2,089 in Lebanon, 23 in Israel and more than a dozen in Gulf Arab states. Thirteen U.S. service members have been killed.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
