Oman - An attack on a ship Thursday in the Strait of Hormuz led the UN to suspend efforts to evacuate mariners trapped in the vital waterway.

The New York Times and other outlets reported that Iran struck a container ship in the strait, and the Iranian agency that claims to regulate traffic there issued a warning after the incident.

"Any passage through routes outside the framework designated by PGSA will not be covered by safe passage guarantees," Persian Gulf Strait Authority said on X.

Iran imposed a blockade of the strait during the war, sparking a global economic shock, and has since said it plans to introduce what it terms maritime service fees.

These developments may complicate negotiations between the US and Iran, which are trying to forge a final agreement after signing a memorandum of understanding to end the conflict that started in late February.

Thursday's attack prompted Arsenio Dominguez, the secretary general of the International Maritime Organization (IMO), a UN agency responsible for marine safety, to announce the suspension of efforts to evacuate the 600 ships and their crews that were trapped by the war.

Dominguez said in a statement that he had paused the evacuation plan "to reconfirm that the necessary safety guarantees continue to be in place for the ships on our evacuation list."

The vessel that was hit on Thursday was not traveling under the IMO's evacuation framework, which began on Tuesday evening, he said.

The British maritime security agency UKMTO said the cargo ship in the strait was "hit on the starboard side by an unknown projectile, causing damage to the bridge," but reporting no casualties. It said the incident occurred just 7.5 nautical miles off Oman's coast.

The White House said it was aware of the reports and was looking into them. "President Trump has been clear that Iran cannot subvert the free flow of traffic in the Strait," a White House official said.