The United States is reportedly running a secret offshore oil-transfer network near the Strait of Hormuz, pursuing a strategy long associated with Iran to maintain the flow of Gulf crude despite Tehran’s blockade of the strategic waterway.The operation, launched in early May, involves transferring oil between ships off the coasts of Oman and the United Arab Emirates before loading it onto large tankers for export, Reuters reported, citing shipping data, satellite imagery and more than a dozen sources familiar with the arrangement.The report estimated that about 90 million barrels of crude oil and petroleum products have moved through the offshore network since the beginning of May, although this is significantly less than the approximately 20 million barrels per day passing through the strait before the conflict.At least 92 ships have participated in this operation, which relies on ships traveling with transponders turned off and lights dimmed; Methods commonly used by Iran’s so-called “Dark Fleet” to evade sanctions and conceal cargo movements.The transfer network emerged after Iran effectively closed access through the Strait of Hormuz during the conflict, disrupting one of the world’s most important energy chokepoints. The waterway typically handles about one-fifth of global oil consumption.Sources told Reuters that the US military coordinated surveillance, compliance checks and transit monitoring for the ships taking part, although there was no indication that US personnel were directly involved in the transfer.The operation has enabled Gulf producers to continue exporting crude despite increased security risks, but analysts warn the system remains vulnerable. “You don’t know when Iran might decide to start using drones or gunboats to prevent those ships from passing through the strait,” said Noam Redan, a senior fellow at the Washington Institute who reviewed the findings for Reuters.The use of the strategy involving previously sanctioned states also attracted the attention of foreign policy observers. “As the old rules weaken, it is ironic that the United States is now taking a page out of the strategies of China, Russia, North Korea, and even Iran, whose so-called ‘dark fleets’ invented these technologies to evade US and UN sanctions,” Michael Froman, president of the Council on Foreign Relations, wrote in a note.