Oil refineries in Japan were shut down following the massive earthquake that occurred near the city of Sendai on 11 March 2011.
Cosmo Oil shut its refinery in the city of Chiba after a fire started at one of the storage tanks.
The Chiba refinery produces 220,000 barrels of oil per day.
JX Nippon Oil & Energy also closed its refineries in Sendai, Kashima and Negishi, which have a combined processing capacity of 600,000 barrels a day.
The shutdown has affected 20% of Japan's 4.6 million barrels a day refining capacity.