Iraq and Saudi Arabia are exporting record volumes of oil. They face growing competition from a resurgent Iran. The impact on trade flows is being felt from Suez to Seoul.

Iraqi exports, along with production, have set repeated new records in recent months – exports averaged 3.376mn b/d in 2015, up 854,000 b/d on 2014, whilst November and December 2015 and January 2016 were the three highest months on record with average volumes just shy of 3.9mn b/d (MEES, 11 March). With the key...