Showa Shell Sekiyu K.K., the Japanese refining unit of Royal Dutch Shell PLC, said Tuesday it will join refiners including Idemitsu Kosan Co. in cutting crude oil processing because of sluggish domestic demand.

Showa Shell will process 8 percent less oil, or 7.95 million kiloliters, a day in the three months ending Sept. 30, it said on its Web site.

It will boost exports by 70 percent for the quarter compared with the same period last year, to about 950,000 kiloliters, the company said.