Trump says US military has blockaded Iranian ports amid Hormuz war

As Donald Trump announced the blockade from the White House, U.S. officials framed it as leverage meant to force Iran to open the Strait of Hormuz and accept a deal aimed at ending a war that has stretched for more than six weeks. Trump said the United States can’t allow Iran to “blackmail or extort the world,” and he suggested Washington had already been called by Tehran’s side and that both countries “want to work a deal.”

MarineTraffic reported that at least two tankers approaching the strait turned around soon after the blockade began. The U.K. Maritime Trade Operations agency said the blockade restricted “the entirety of the Iranian coastline, including ports and energy infrastructure,” while noting that transit through the strait between non-Iranian places was not reported to be impeded, although ships “may encounter military presence.” The arrangement, and the immediate effect on some traffic, set up what the reporting described as a high-stakes showdown with risks for shipping and for whether any ceasefire could hold.

U.S. Central Command said 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 notice also indicated a limited carve-out for travel between non-Iranian ports, even as it marked the start of enforcement that Trump had previously threatened more broadly.

The announcement came after ceasefire talks between the United States and Iran ended without agreement over the weekend, following marathon discussions in Pakistan. Trump’s efforts to open a path to a permanent end to the conflict have run into hurdles over issues including Iran’s nuclear program, while U.S. Vice President JD Vance told FOX News Channel’s “Special Report” that the talks stalled after Iran refused to accept American terms on refraining from developing a nuclear weapon.

Iran responded with threats aimed at U.S.-allied countries and across the regional maritime space. Islamic Republic of Iran Broadcasting reported that “Security in the Persian Gulf and the Sea of Oman is either for everyone or for NO ONE,” and said “An Iranian military statement” added: “NO PORT in the region will be safe.” In a post on X, Ebrahim Rezaei, a spokesperson for Iran’s parliament’s National Security Commission, dismissed the U.S. threat of a blockade as “more bluffing than reality,” saying it would make conditions “more complicated” and increase turbulence in markets. Parliament speaker Mohammad Bagher Qalibaf also addressed Trump, saying: “If you fight, we will fight.”

Officials also cautioned about how enforcement would work in practice and what legal standards might apply. Todd Huntley, a retired Navy captain and director of Georgetown University’s national security law program, said: “How it is carried out will determine whether it is lawful or not.” The legal experts were also expected to watch whether the U.S. allowed humanitarian aid to reach Iran, as international law requires blockades to be impartially enforced.

Talks between Washington and Tehran were described as still moving forward even after the weekend’s negotiations ended without a deal. Two U.S. officials and a person familiar with the development said Monday that discussions about a second round of in-person negotiations were underway, and a diplomat from a mediating country said Tehran and Washington agreed to more talks. All four spoke on condition of anonymity to discuss sensitive diplomatic negotiations.

The standoff has also fed market and pricing pressures tied to the strait’s global role in oil shipments. The reporting said Iran’s effective closure of the strait has sent oil prices higher, with the price of Brent crude hovering just under $100 per barrel Monday, compared with roughly $70 per barrel before the war. Lloyd’s List Intelligence reported that Iran’s threatened closure halted limited ship traffic that had resumed in the strait since the ceasefire, with Marine trackers showing over 40 commercial ships had crossed since the start of the ceasefire last week—down from 100 or more vessel passages per day before the war.

In Washington, Trump also sought to signal the military posture behind the blockade. In a social media message, Trump said Iran’s navy had been “completely obliterated” but still had “fast attack ships,” warning that “if any of these ships come anywhere close to our BLOCKADE, they will be immediately ELIMINATED.” The message and the operational details from CENTCOM increased the prospect of rapid escalation at sea even as diplomacy continued off the water.

At the same time, Iranian officials linked the dispute to broader grievances. Iran’s representative to the United Nations, Amir-Saeid Iravani, demanded compensation from five Middle Eastern countries—Bahrain, Saudi Arabia, Qatar, Jordan and the United Arab Emirates—that Iran said violated international law by aiding the war effort against it, state-run media reported.

The ceasefire itself was already nearing a deadline. The ceasefire expires April 22, and 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, while the reporting said 13 U.S. service members have been killed.