Fraudulent messages promising safe passage through the Strait of Hormuz in exchange for cryptocurrency ​have been sent to some shipping companies whose vessels are ‌stranded west of the waterway, Greek maritime risk management ​firm MARISKS has warned.

The U.S. has ⁠maintained its blockade of Iranian ports, while Iran has lifted and then re-imposed its blockade of the Strait of Hormuz, ‌through which roughly a fifth of the world’s oil and liquefied natural gas passed before ‌war broke out in the Middle East.

Amid ceasefire ‌talks, ⁠Tehran, which controls the chokepoint, has proposed tolls ⁠on vessels to safely transit.

MARISKS on Monday issued an alert warning shipowners that unknown actors, claiming to represent Iranian authorities, ​had sent some shipping companies ‌a message demanding transit fees in cryptocurrencies, Bitcoin or Tether, for “clearance”.

“These specific messages are a scam,” the firm said, adding the message was not sent ‌by Iranian authorities.

There was no immediate comment from ​Tehran.

Hundreds of ships and about 20,000 seafarers remain stranded in the Gulf.

On April 18, ⁠when Iran briefly opened the strait subject to checks, ships tried to pass but at least two of ‌them, including a tanker, reported that Iranian boats had fired shots at them, forcing the vessels to turn around.

MARISKS said that it believed that at least one of the vessels, which tried to exit the strait on Saturday and was hit by gunfire, ‌was a victim of the fraud.

Reuters was not able to ​verify the information or track companies that had received the message.

“After providing the documents ⁠and assessing your eligibility by the Iranian Security Services, we ⁠will be able to determine the fee to be paid in cryptocurrency (BTC or USDT). Only then ‌will your vessel be able to transit the strait unimpeded at the pre-agreed time,” said the ​message cited by MARISKS.

Published on April 21, 2026