The US has warned shipping companies they could face sanctions if they pay Iran for safe passage through the Strait of Hormuz.

An alert on Friday by the US Office of Foreign Assets Control (OFAC) warned US persons and companies were generally banned from paying Iranian government entities, and non-US persons may risk exposure to sanctions if they pay.

“Maritime industry participants involved with vessels calling at Iranian ports face significant sanctions risk under multiple sanctions authorities targeting Iran’s shipping sector and ports”, OFAC said.

Iran has severely limited traffic through the strait since the war began in February. The US has also enforced a naval blockade on Iranian ports.