Iran live updates: US blockade of Iran's Strait of Hormuz ports to begin Monday

The spokesperson for Iran's joint military command at Khatam al-Anbiya Central Headquarters said Monday that if the security of Iranian ports in the Persian Gulf and the Sea of Oman is threatened, "no port in the Persian Gulf and the Sea of Oman will be safe."

"Enemy-affiliated" vessels will not have the right to pass through the Strait of Hormuz, while other vessels will continue to be allowed transit "in accordance with the regulations of the Islamic Republic of Iran's armed forces," the spokesperson said, as quoted by Iran's state television Telegram channel.

"Given the continued threats," he said, the Islamic Republic will also implement "a permanent mechanism" to control the Strait of Hormuz, even after the war.

The price of oil again climbed on Monday, after the United States said it would begin a blockade of the Strait of Hormuz.

The blockade -- which was expected to begin at 10 a.m. ET, according to U.S. Central Command -- appeared poised to continue the disruption of the vital maritime passageway off the southern Iranian coast, through which some 20% of the world's oil supply is shipped.

Brent crude oil prices, a benchmark for global trading, climbed about 8% by 5 a.m. ET on Monday. It traded at more than $102 a barrel for deliveries in June.

U.S. crude prices for May contracts also advanced about 8% in early trading, climbing to about $103 per barrel.

U.S. forces will begin a blockade of maritime traffic to and from Iranian ports Monday morning, according to U.S. Central Command.

"U.S. Central Command (CENTCOM) forces will begin implementing a blockade of all maritime traffic entering and exiting Iranian ports on April 13 at 10 a.m. ET, in accordance with the President's proclamation," according to a CENTCOM statement late Sunday afternoon.

Guided-missile destroyer USS Frank E. Petersen Jr. (DDG 121) sails in the Arabian Sea during Operation Epic Fury, on March 18, 2026.
U.S. Navy
"The blockade will be enforced impartially against vessels of all nations entering or departing Iranian ports and coastal areas, including all Iranian ports on the Arabian Gulf and Gulf of Oman," the statement continued, adding that CENTCOM forces "will not impede freedom of navigation for vessels transiting the Strait of Hormuz to and from non-Iranian ports."

President Donald Trump said Sunday morning in a post on his social media platform that the U.S. will "immediately" begin a blockade of the Strait of Hormuz, following the failure of peace negotiations between the U.S. and Iran.

Commercial mariners will be provided with additional information prior to the start of the blockade, according to CENTCOM, which also advised "all mariners" to monitor advisory broadcasts and contact U.S. naval forces "when operating in the Gulf of Oman and Strait of Hormuz approaches."

A U.S. official close to the U.S.-Iran negotiations this weekend tells ABC News that the two sides went home Saturday after failing to agree on several key issues, despite President Donald Trump's statements Sunday in a social media post that the "meeting went well" and "most points were agreed to," save for Iran's alleged refusal to abandon their nuclear ambitions.

According to the U.S. official, the key points on which Iran would not concede include ending all uranium enrichment, dismantling all major nuclear enrichment facilities and allowing the U.S. to retrieve any highly enriched uranium Iran may possess; accepting a broader peace, security and de-escalation framework that includes regional allies; ending funding for terrorist proxies Hamas, Hezbollah and the Houthis; and fully opening the Strait of Hormuz and not charging tolls for passage.

All of these points were red lines for the U.S., the official said.

-ABC News' Hannah Demissie and Justin Fishel