U.S. Navy Blockades Iranian Ports at Strait of Hormuz as Talks Collapse

Trump orders warships to seal off Iranian oil exports after 21-hour Islamabad negotiations fail, sending Brent crude above $100 and drawing threats of retaliation from Tehran

The U.S. Navy began enforcing a blockade of Iranian ports at the Strait of Hormuz at 10 a.m. Eastern time Monday, less than 48 hours after a 21-hour round of U.S.-Iran talks in Islamabad, Pakistan, broke up without an agreement. President Trump, who announced the move in a Truth Social post Sunday and confirmed it in a Fox News interview, ordered U.S. warships to halt all vessels entering or leaving Iranian ports and warned that any Iranian ship that approaches the cordon will be "immediately ELIMINATED."

The blockade marks the sharpest American escalation since the U.S.-Israel war with Iran began Feb. 28 and puts Washington on a collision course with a waterway that carries roughly a fifth of the world's energy shipments. Brent crude surged more than 7 percent and traded above $100 a barrel for the first time in a week. The conditional two-week ceasefire Washington and Tehran struck last Wednesday, which had been meant to reopen the strait, is now in doubt.

What broke down

Vice President JD Vance led the U.S. delegation that spent 21 hours on the ground in Islamabad on Saturday and into Sunday morning. Vance said afterward that Iran chose "not to accept our terms" and described the U.S. offer as a "very simple proposal" and "final and best offer." Iranian Foreign Minister Abbas Araghchi said Iran had negotiated "in good faith" and accused the U.S. of introducing "maximalist demands" when a deal appeared imminent. Trump, asked Sunday what he wanted from Tehran, said, "I want everything. I don't want 90%. I don't want 95%. I told them I want everything." U.S. officials say the core demand is that Iran surrender its highly enriched uranium.

The cordon

U.S. Central Command said the blockade applies only to ships going to or from Iranian ports and will not impede transits to and from non-Iranian ports. The U.S. has roughly 15 ships in the region, including one aircraft carrier group with another nearby, NPR national security correspondent Greg Myre reported. The United Kingdom Maritime Trade Operations issued a notice warning that "maritime access restrictions are being enforced affecting Iranian ports and coastal areas, including locations along the Arabian Gulf, Gulf of Oman, and the Arabian Sea east of the Strait of Hormuz."

Retired Adm. James Foggo, a former commander of U.S. naval forces for Europe and Africa and now dean of the Center for Maritime Strategy, said Aegis-class destroyers can track vessels for hundreds of miles and stop suspect ships through hailing and vessel-boarding, search and seizure. Foggo said he was "supremely confident" in the Navy's ability to execute the mission. He also noted the mine threat is real: during the 1991 Gulf War, three U.S. ships struck mines in the northern Arabian Sea, and the frigate Samuel B. Roberts nearly sank.

The toll

Shipping through the strait has been near a standstill since the war began. Iran has kept limited traffic moving and, according to Trump, has charged foreign vessels as much as $2 million per transit, a practice he has called "WORLD EXTORTION." Foggo said that if the tolling were extrapolated to a hundred ships a day across a full year, "that's a profit of $73 billion," more than the Navy's shipbuilding budget. Maritime intelligence firm Windward said more than 58 million barrels of Iranian crude have left Kharg Island since March 1, with more than 90 percent bound for China.

On the markets

The commodity shock extends well beyond fuel. David Satterfield, a former U.S. special envoy for Middle East humanitarian issues, told the BBC the strait also carries "about 30% of the world's aluminium," about 30 percent of the world's helium, up to 50 percent of global fertilizer feedstocks and about 17 percent of polymers. European equities slipped, with Britain's FTSE 100 down 0.35 percent and Germany's DAX off 1 percent. U.S. stocks recovered from early losses, with the S&P 500 up 0.6 percent on Monday afternoon. Neil Shearing, group chief economist at Capital Economics, said the blockade may be "designed to pressure Beijing into playing a more active role in mediating a ceasefire and reopening full trade flows through the Strait."

The counterparty

Iran's Unified Command of the Armed Forces called the U.S. restrictions "illegal and constitutes piracy" and said Tehran would impose a "permanent mechanism to control the Strait of Hormuz." Iran's Revolutionary Guard warned that any U.S. warship approaching the waterway would be treated as a ceasefire violation and met with a "severe response." China's Foreign Minister Wang Yi opposed the blockade and urged broader ceasefire efforts. French President Emmanuel Macron said he would convene a conference with Britain in the coming days on a "peaceful multinational mission aimed at restoring freedom of navigation."

Maritime security expert Ian Ralby told PBS NewsHour the blockade represents "an escalation by the United States" using "a law of naval warfare construct" that is likely to trigger retaliation and harm neutral vessels. Weeks of U.S. and Israeli bombing did not force Iran to reopen the strait, and Tehran retains drones and mines.

The two-week ceasefire that the blockade threatens to end expires April 22. No follow-on talks have been scheduled.