The Nikkei 225 index at the Tokyo Stock Exchange jumped 2.03 percent, or 200.89 points, to end the morning session at 10,099.97. The Topix index of all first-section shares added 1.81 percent, or 15.33 points, to 860.66. On Wall Street the Dow zoomed past the 13,000 mark, driven by soaring bank shares after JPMorgan Chase's announcement of a huge share buyback and dividend hike after it passed a crucial stress test by the Federal Reserve. The Dow Jones Industrial Average closed up 1.68 percent to 13,177.68, the blue-chip index's best closing level since December 2007. Japanese stocks would likely benefit from the weakening yen, said Daiwa Capital Markets, predicting that the greenback would climb further against the Japanese unit. "All in all, we think the dollar could climb to 83.50-85.00 (yen)," it said in a note to clients. "Japanese shares may stage a temporary pullback, but we still believe they are on a medium-term uptrend," Daiwa added. The yen stood at 83.14 against the dollar, slipping from 82.90 in New York Tuesday. The greenback briefly touched 83.21 yen in Tokyo morning trade, its highest level since April last year. The euro, meanwhile, bought $1.3068 and 108.63 yen, compared with $1.3075 and 108.38 yen in New York. Markets were buoyed after the US central bank, following its monthly policy meeting Tuesday, upgraded its view of the world's number one economy, saying the jobs market and consumer and business spending had improved since January. The Federal Reserve also kept ultra-low interest rates unchanged. Adding to the optimism was a surprise move by Fitch to raise Greece's credit rating out of default. Among major shares, Honda Motor added 2.90 percent to 3,190 yen following a report that the company was planning a new auto factory in Indonesia, after it announced Tuesday it would build a new motorcycle plant in the country. Sony surged 5.41 percent to 1,794 yen, while heavyweight Mitsubishi UFJ Financial Group rose 2.37 percent to 432 yen.