Chinese state giant CNPC announced on 14 December that it had signed a strategic cooperation agreement with Abu Dhabi state firm Mubadala Petroleum to establish a $10bn fund to invest in global projects.

This is the latest instance of Abu Dhabi seeking to bolster commercial relations with key crude oil customers in Asia such as China, which imported an average of 230,000 b/d of Emirati crude in the first 10 months of 2015, making the UAE China’s eighth biggest supplier. Supplies hit...