The US Treasury has warned shippers that paying tolls to Iran for passage through the Strait of Hormuz, including charitable donations, may lead to punitive sanctions.
The Strait of Hormuz is a vital maritime route, with 20% of the world's seaborne crude oil and liquefied natural gas flows passing through it.
Tehran has proposed fees or tolls on vessels, as part of proposals to end the war with Israel and the US.
The US Treasury's Office of Foreign Assets Control (OFAC) has advised companies that paying the tolls puts them at risk, and that payments disguised through charity or indirect payments are not allowed.
OFAC has imposed fresh sanctions on three Iranian foreign currency exchange houses and an oil products tanker, and warned that demands for payments may include several options, including fiat currency, digital assets, and in-kind payments.
