Toyota Motor Corp., Japan's largest carmaker, fell 0.2 percent, and Sony Corp. declined 0.4 percent.
Mitsui Chemicals Inc., Japan's second-largest ethylene producer, will halve its domestic production capacity, and Kawasaki Heavy Industries Ltd., the country's second-largest maker of heavy machinery, will cancel plans to build an industrial robot factory, the Nikkei newspaper said in separate articles over the weekend.
The Nikkei 225 Stock Average fell 25.09, or 0.2 percent, to 13,212.80, while the broader Topix index dropped 2.16, or 0.2 percent, to 1,295.72 as of 9:02 a.m.
Kawasaki Heavy fell 2.5 percent to 273 yen, while Mitsui Chemicals rose 2.1 percent to 492 yen.
Leaders of the U.S., Japan, Germany, the U.K., France, Italy, Russia and Canada are meeting from today to July 9 in Toyako, Northern Japan. Curbing the rise in energy and food prices is among items on the summit agenda.
The Group of Eight leaders should encourage oil-producing countries to boost output to prevent an economic slowdown, French President Nicolas Sarkozy said in an interview published today in the Yomiuri Shimbun.
Crude oil, which has doubled in the past year, traded at $144.20 at 6:02 a.m. in Singapore after climbing to a record $145.85 on July 3.