The US Treasury Department has imposed the largest sanctions on Iran since the past seven years.

The measures are aimed at combating a "shadow fleet" that illegally transports domestic and Russian oil. More than 50 individuals and entities and more than 50 ships have been blacklisted, which are part of a network controlled by Mohammad Hossein Shamkhani, an oil trader and son of an adviser to Iran's Supreme Leader Ayatollah Ali Khamenei.

The US Treasury Department said that Shamkhani uses his father's corruption and political influence to control a huge fleet of tankers and container ships. This network transports oil and petroleum products from Iran and Russia, as well as other cargoes to buyers around the world and generates tens of billions of dollars in profits that go to fund Iran’s dangerous activities, the department emphasized.

In particular, the Dubai-based Milavous Group, Ocean Leonid Investments, and Crios Shipping were sanctioned.

In addition, the US Treasury Department noted that the Shamkhani family spends illegally obtained funds around the world to acquire exclusive real estate and foreign passports, which enables blacklisted individuals to hide their ties to Iran and further their corrupt schemes when conducting business abroad.

Shamkhani’s Milavous Group coordinates the activities of ships sailing under the flags of Liberia and Panama and sells up to 300,000 barrels of oil per day, generating about $400 million in annual revenue.