In the arrangement, some of the officials said, an Iranian-controlled company registers the sale of oil to a Chinese buyer controlled by state-owned oil trader Zhuhai Zhenrong, a U.S. sanctions target. ? The Chinese buyer, in return, deposits hundreds of millions of dollars each month with Chuxin, officials said. Chuxin then delivers the funds to Chinese contractors that perform engineering work in Iran, in projects whose financing is insured by Sinosure. Sinosure serves as the financial glue that holds the projects together.