Idemitsu was forced to shut down all units at its Tomakomai refinery last September following fires at two of the oil tanks, which were later attributed to an earthquake that struck the region.

According to a spokesperson for Idemitsu, "The 12 tanks, from which Idemitsu Kosan will resume shipping operations, are mostly used for A- and C-type fuel oil and LPG."

However, the spokesperson could not confirm the exact time for the restart of the refinery's main units, which includes a 140,000-barrel-a-day crude distillation unit amongst its arsenal.

Aside from giving Idemitsu the all clear, the Tomakomai city government has also given the company approval to use the seven shipping berths located at the refinery. This means that Idemitsu can also resume petroleum deliveries via coastal tankers.