Nikkei rose 1.27 percent in early trading Monday, triggered by a weaker yen.
The 225-issue Nikkei Stock Average gained 118.65 points, or 1. 27 percent, from Thursday's close in the first 15 minutes to 9,485. 45.
The broader Topix index of all First Section issues on the Tokyo Stock Exchange added 10.35 points, or 1.33 percent, to 786. 78. The market was closed on Friday for a national holiday.