Tokyo stocks ended 1.03 percent higher in the morning session of Wednesday as market sentiment was lifted by the yen's weakness.
The 225-issue Nikkei Stock Average gained 182.69 points from Tuesday to 17,845.91 after briefly rising to 17,881.76, its highest level on an intraday basis since July 24, 2007.
The broader Topix index of all First Section issues on the Tokyo Stock Exchange gained 9.03 points, or 0.63 percent, at 1,436. 88.
Major gainers included precision instruments, brokerage and steel issues.