The United States imposes fresh sanctions on Iran aimed at its so-called “shadow fleet” of oil tankers. The U.S. Treasury designates individuals, companies and networks involved in transporting Iranian crude, oil products and petrochemicals, and specifically targets 17 vessels, according to the Treasury Department.

The measures are part of a broader U.S. pressure campaign under “Operation Economic Outcast,” which seeks to cut off funding for Iran-related military and other activities. Multiple outlets report that the sanctioned tankers have carried millions of barrels of Iranian crude and related products to markets in Asia, particularly South and East Asia. Coverage also notes that the sanctions extend to the owners and associated companies operating in Iran’s petroleum and petrochemical sectors. Some reporting characterizes the step as neutralizing most or a large share of what remains of the fleet, reflecting the U.S. view that the additional designations will disrupt the network used to move Iranian energy supplies despite sanctions.