The U.S. Department of the Treasury announced on Wednesday that it has imposed sanctions on over a dozen entities and vessels linked to the transportation of Iranian crude oil and liquid petroleum gas to Syria and East Asia, acting on behalf of Iran’s Revolutionary Guards and Hezbollah.

Among the sanctioned vessels are four ships tied to Syrian shipping magnate Abdul Jalil Mallah, who was previously sanctioned by the U.S. in 2021, as well as his brother, Luay al-Mallah, who was also designated under U.S. sanctions on the same day.

The Treasury Department stated that the Mallah brothers have “continued to utilize their shipping operations to facilitate Iran’s harmful activities and those of its affiliates.”

Bradley T. Smith, the acting under secretary of the Treasury for Terrorism and Financial Intelligence, emphasized in the statement that “Iran remains heavily dependent on the illicit sale of oil and liquid petroleum gas by the Revolutionary Guards and Lebanese Hezbollah to finance its terrorist proxies and destabilizing actions.”