U.S. Treasury warns all shippers not to pay Iran a "toll" for safe passage of Strait of Hormuz

The U.S. Treasury issued a notice on Friday warning that any individual or company, American or foreign, that pays the Iranian regime a "toll" for safe passage through the Strait of Hormuz was at risk of violating U.S. sanctions against Iran.

"The Office of Foreign Assets Control (OFAC) is aware of Iranian threats to shipping and demands for 'toll' payments to receive safe passage through the international Strait of Hormuz," the Treasury office said in a note posted on its website, noting that such payments could be sought in hard currency, crypto currencies, "or other in-kind payments, such as nominally charitable donations made to the Iranian Red Crescent Society, Bonyad Mostazafan, or Iranian embassy accounts."

"OFAC is issuing this alert to warn U.S. and non-U.S. persons about the sanctions risks of making these payments to, or soliciting guarantees from, the Iranian regime for safe passage," the statement said. "These risks exist regardless of payment method."

Iranian authorities currently demand that any commercial vessel must coordinate with the country's military to ensure safe passage through the vital shipping lane — under the threat of violence and seizure. 

The threat, which Iran has maintained to varying degrees since the U.S. and Israel launched their war with the country on Feb. 28, has reduced shipping traffic in and out of the Persian Gulf by 90%, according to the U.K. navy.

A handful of international vessels have transited the strait in coordination with Iran, but none have acknowledged paying a fee.