TOKYO (Reuters) - Japanese refiner Idemitsu Kosan Co Ltd (5019.T) said on Monday it has completed its planned acquisition of 31.3 percent of rival Showa Shell Sekiyu KK (5002.T) from Royal Dutch Shell PLC (RDSa.L).
Earlier in the day, Japan's anti-monopoly regulator approved Idemitsu's plan to acquire the stake.
In a filing at the stock exchange, Idemitsu said it paid 1,350 yen a share, or a total of 159 billion yen (1.08 billion pounds).
The refiner had originally planned to buy 33.3 percent from Royal Dutch Shell.
Reporting by Taiga Uranaka