Tokyo stocks ended 1.04 percent higher in the morning session of Wednesday, with the index climbing above the 16,000 threshold temporarily, bolstered by gains of U.S. stocks and the yen's weaken.
The 225-issue Nikkei Stock Average was up 163.97 points, at 15, 978.34.
The broader Topix index of all First Section issues on the Tokyo Stock Exchange rose 10.68 points, or 0.83 percent, to 1,293. 93.
Gainers were led by machinery, metal and rubber sectors, while food, steel and fishery and agriculture sectors headed lower.