Sanctions enforcement risk rises

Washington is widening sanctions pressure on Iran’s oil trade, while Chinese buying remains the central enforcement test. (treasury.gov) On April 16, 2025, the United States Treasury sanctioned Shandong Shengxing Chemical, a China-based independent refinery, and said it had bought more than $1 billion of Iranian crude. Treasury said the action was its second against a so-called teapot refinery and the sixth round targeting Iranian oil sales under President Donald Trump’s February 2025 “maximum pressure” order. (treasury.gov) The same day, the Office of Foreign Assets Control updated its shipping advisory and added new companies and tankers to its sanctions list, including Panama-, Hong Kong-, Malaysia-, and Marshall Islands-linked entities. The advisory told shipowners, insurers, ports, and traders to watch for tactics such as opaque ownership and ship-to-ship transfers used to mask Iranian cargoes. (ofac.treasury.gov) Congressional Research Service said on March 28, 2025 that nearly all Iranian petroleum exports since 2021 had reportedly gone to China. The report said traders used a range of evasive techniques and noted that Shandong Port Group had announced in January 2025 that it would bar United States-sanctioned vessels, even as other Chinese ports continued handling Iranian-linked cargoes. (congress.gov) That leaves sanctions risk concentrated far beyond the oil seller and the refinery buyer. Treasury’s April 2025 advisory was written for the full maritime chain, including brokers, ship managers, flag registries, insurers, banks, and port operators. (ofac.treasury.gov) For manufacturers, the practical issue is not only crude supply. It is whether a tanker, terminal, warehouse, bank payment, or marine insurance policy touches a sanctioned counterparty and turns an ordinary shipment into a compliance problem. (ofac.treasury.gov; congress.gov) The United States Energy Information Administration said in its August 2025 report that data on Iranian exports are estimates because the trade is hard to track. That opacity is part of the problem for freight and supply-chain teams: the cargo can move, but the paperwork, ownership trail, and port history may stay murky. (eia.gov) Washington signaled another step on April 14, 2026, when Reuters reported that the Trump administration would not renew a 30-day waiver covering Iranian oil at sea. On April 16, 2026, Reuters also reported Treasury Secretary Scott Bessent warning that buyers of Iranian oil and banks holding Iranian funds could face secondary sanctions. (msn.com; economictimes.indiatimes.com) Chinese purchases are the unresolved variable. Reuters reported on April 16, 2026 that Bessent said China had been buying more than 80% of Iran’s shipped oil and that Washington believed a pause could follow tighter enforcement, but Beijing had not publicly committed to that outcome in the reporting reviewed here. (economictimes.indiatimes.com) The result is a market where the legal risk can spread faster than the barrels. As Washington adds names to sanctions lists and warns banks, the next pressure point is likely to be screening, insurance, and payment checks across the shipping networks that move oil and the goods made from it. (treasury.gov; ofac.treasury.gov)