The US Treasury has warned financial institutions that they could face sanctions if they engage in dealings with Chinese refineries that process Iranian oil. The move comes as part of a "maximum pressure" campaign against Iran, imposed by U.S. President Donald Trump in February. The Treasury has urged financial institutions to avoid facilitating transactions involving independent refineries, known as "teapots," that import Iranian oil, as these transactions could expose them to sanctions. It also urged institutions to conduct enhanced due diligence on transactions involving China-based refineries and other Asia-and Middle East-based entities involved in Iran's oil supply chain to avoid potential sanctions. This comes as Iran's main export terminal nears its storage capacity, which could force Tehran to cut production and lose about $170 million in daily revenue.