The Peoples' Bank of China, China's central bank, issued Administrative Rules on Pilot Program of Renminbi Settlement of Cross-border Trade Transactions in order to facilitate trade, to make sure the pilot renminbi settlement of cross-border trade transactions is smoothly executed, to regulate the behaviors of pilot enterprises and commercial banks, and to prevent risks arising from the above business. 

These Rules applies to renminbi settlement of cross-border trade transactions in the pilot areas as approved by the State Council, which includes Shanghai, Guangzhou, Shenzhen, Zhuhai and Dongguan.  It regulates the trading partners as well related commercial banks.  Choosing yuan settlement is on voluntary basis.