The U.S. Treasury unveiled a fresh wave of sanctions on Friday, targeting 40 shipping firms and vessels tied to Iran’s shadow fleet. The move follows a brief lift in March that allowed limited Iranian oil sales. By cracking down again, Washington aims to cut a key revenue stream for Tehran and its economy.

In a parallel move, the department slapped sanctions on Hengli Petrochemical Refinery, China’s second‑largest independent refining plant and a major importer of Iranian crude. The refinery has purchased billions of dollars’ worth of oil from the Revolutionary Guards Corp, a key conduit for Tehran’s exports to Asia in recent months, and global markets.

Treasury Secretary Scott Bessent warned that any vessel or intermediary aiding these flows risks exposure to U.S. sanctions. Washington’s strategy mirrors the earlier blockade of the Strait of Hormuz, tightening pressure on Iran’s ability to sell oil abroad. The crackdown targets the network that lets Tehran sidestep Western restrictions and global markets for economic stability.

The sanctions hit a critical node in Iran’s oil supply chain, potentially slashing the country’s export earnings by tens of billions annually. Investors in energy markets will monitor how quickly the shadow fleet adapts and whether alternative routes emerge. For now, the U.S. maintains a hard line, tightening its grip on Tehran’s revenue lifeline today.