A businessman sanctioned by the US for allegedly helping smuggle weapons on behalf of Iran's Islamic Revolutionary Guards Corps (IRGC) has business interests in a tanker that illicitly moved Iranian oil, an investigation by <em>The National </em>has found. On Friday, the US Department of the Treasury blacklisted Iraqi-Iranian dual national Amir Dianat for his reported involvement in the regional smuggling efforts of the elite Quds Force of the IRGC, including “efforts aimed at the shipment of weapons including missiles”. Mr Dianat's involvement in smuggling operations included efforts aimed at moving matiriel from Iran to Yemen, the department said in a statement. The US also sanctioned Taif Mining Services LLC, saying that Mr Dianat used the Oman-based firm to procure an oil tanker and develop “additional illicit business opportunities to generate revenue” for the Quds Force. Taif Mining Services acquired the <em>Nautic</em> Suezmax oil tanker in late October 2019, which was subsequently renamed to <em>Gulf Sky</em>, according to maritime records seen by <em>The National</em>. The Dominican Republic-flagged vessel went on to transport Iranian crude oil, according to Samir Madani, the co-founder of the TankerTrackers.com service that monitors the Iranian petroleum trade. Using satellite imagery, Mr Madani uncovered that the <em>Gulf Sky </em>pulled up alongside a domestic Iranian oil tanker from December 5 to 6 to conduct a ship-to-ship transfer of petroleum in Iran's territorial water. The <em>Gulf Sky</em>'s location transponder was turned off during the transfer, a common practice used by Iran-linked "ghost ships" to obscure their activities. On December 7 the tanker came online again and sailed through the Strait of Hormuz to arrive at the Khor Fakkan anchorage off the coast of Sharjah before docking at the Fujairah anchorage on December 15. Records reviewed by <em>The National </em>reveal that, while the <em>Gulf Sky </em>tanker ostensibly changed ownership weeks after its ship-to-ship transfer, this was yet another sleight-of-hand involving the vessel. Taif Shipping Services, based in Oman, acquired the vessel in January 2020 from Mr Dianat’s Taif Mining Services, according to the UN’s International Maritime Organisation. However, Omani government records show that Taif Mining Services on December 31, 2019 had changed its name to Taif Shipping Services. Washington’s sanctions on Mr Dianat and his company are the latest in a slew of US Treasury Department attempts to stymie Iranian oil exports. In September 2019, the US took sanctions action against what it called a “vast Iranian petroleum shipping network” that was allegedly moving oil from Iran to Syria at the behest of the IRGC’s Quds Force. According to the US, “senior IRGC-QF official and former Iranian Minister of Petroleum Rostam Qasemi oversees this sprawling network, which features dozens of ship managers, vessels, and facilitators”. In its latest press release, the US Treasury accused Mr Dianat of being an associate of Mr Qasemi, without elaborating further on their ties. “The IRGC-QF has relied on Dianat to secure entry for vessels carrying IRGC-QF shipments and has used his business connections to facilitate logistics requirements. Dianat has been directly involved in IRGC-QF efforts to smuggle shipments from Iran to Yemen,” the US said.