U.S.-flagged ships have been advised to stay "as far as possible" from Iranian waters when navigating the Strait of Hormuz as tensions between Washington and Tehran remain elevated.
In a notice issued Monday, the U.S. Maritime Administration said ship captains should decline permission for Iranian forces to board U.S. vessels.
Boarding attempts, including moves to force commercial vessels into Iranian waters through small boats and helicopters, have occured as recently as Feb. 3, the agency under the Department of Transportation said.
Should Iranian forces board a U.S.-flagged commercial vessel, crews were advised not to "forcibly resist the boarding party," the notice said. It added that refraining from forcible resistance does not imply consent or agreement to that boarding.
The advisory recommended that ships transiting eastbound in the Strait of Hormuz stay close to the Omani side of the waterway.
The guidance followed a round of indirect talks between the U.S. and Iran held in Oman on Friday, centered on how to approach discussions over Tehran's nuclear program. The meeting marked the first talks between the two countries since U.S. bombers struck three Iranian nuclear sites during a 12-day war with Iran last June.
Iran's President Masoud Pezeshkian described the talks as "a step forward," while signaling they would be the opening stage of a longer diplomatic process rather than a path to a quick resolution. Iranian Foreign Minister Abbas Araghchi also told state media that the talks were a "good start."
President Donald Trump said the Oman talks were "very good" and that more sessions were planned, even as he warned Iran that failure to reach a deal would carry "very steep" consequences for Iran.
Israeli Prime Minister Benjamin Netanyahu is set to meet Trump in Washington on Wednesday to discuss the U.S.-Iran talks. Israel, a close U.S. ally, has lobbied Washington to dismantle Iran's nuclear program, curb its ballistic missile program and end its support for militant groups in the region.
The Strait of Hormuz, a narrow waterway connecting the Persian Gulf and the Arabian Sea, has returned to the spotlight this year after Trump warned of possible military action against Tehran.
About 13 million barrels per day of crude oil transited the Strait of Hormuz in 2025, according to data from market intelligence Kpler, accounting for nearly a third of global seaborne crude flows.
Any disruption to those flows would ripple through global energy markets. Iran has in the past threatened to close the Strait during past confrontations, raising the prospect of higher oil prices.
