‘Business as usual’ for Iranian shadow fleet passing through Southeast Asia, say analysts

Malaysia has, in recent years, been identified as a hub for illegal STS transfers. According to United Against Nuclear Iran (UANI), instances of such activity involving sanctioned Iranian oil in Malaysian waters rose from 280 in 2023 to 679 in 2025, driven largely by demand from China. . . . UANI, a US-based advocacy group that monitors sanctions evasion, said the Iranian shadow fleet has continued its operations in South-east Asian waters. Most recently, UANI senior adviser Charlie Brown observed that the Iranian tanker Amber was near two US Navy littoral combat ships that had arrived in Penang. He said the tanker had been spotted in Bandar Abbas, Iran, on March 4, four days after the start of the US-Israeli air strikes against Tehran, before passing through the Strait of Malacca and the Singapore Strait on March 15. On what possible action the US naval ships may have taken, he said: “The US won’t sink any of these ships, even Iranian-flagged vessels. They could seize as war prize the Iranian-flagged ships in certain circumstances.”