China has blocked MasterCard from processing credit card transactions in renminbi, raising concerns about Beijing's willingness to fully open up the sector after the World Trade Organisation found that it unfairly restricted foreign card companies http://link.ft.com/r/4RNQTT/IEHNBH/OJ2XU6/FK5GUO/6A3I9B/KI/h?a1=2013&a2=6&a3=2