The war between Israel and Iran has raised concerns that Iran could try to close the Strait of Hormuz, the world’s most important oil chokepoint.

Naval forces in the Middle East warned that ships, especially U.S.-linked ones, could be at heightened risk after the U.S. strikes on Iran.

Iran has threatened to close the Strait of Hormuz, in what would serve as another act of retaliation after the U.S. launched strikes on three key Iranian nuclear facilities over the weekend.