Tokyo stocks closed higher Wednesday on a weaker yen, after shares dipped in and out of positive territory amid caution over the unfolding impact of the March 11 disasters, dealers said.
The Nikkei 225 index added 85.92 points, or 0.90 percent, to 9,641.18. The Topix added 6.08 points, or 0.73 percent, to 844.59.
The yen rallied on Tuesday after Japan raised its nuclear crisis level to 7 - the highest international severity level - from 5.
But on Wednesday the currency reversed course, lifting stocks firmly into positive territory.
The Japanese unit eased to 84.03 to the dollar from 83.56. It was at 121.89 to the euro from 120.98 Tuesday.
Automakers benefitted. Toyota closed 1.38 percent higher at 3,285 yen and Honda Motor rose 3.31 percent to 2,957. Nissan Motor added 2.87 percent at 716.
They were also lifted by a report that key provider of microcontrollers will restart production soon.
Renesas Electronics finished 7.55 percent higher at 698, buoyed by a Nikkei report that the chipmaker will start work again at a damaged plant northeast of Tokyo one month ahead of schedule.
"This is a big deal as Renesas is a huge supplier and major automakers depend on it," Tsuyoshi Segawa, equity strategist at Mizuho Securities, told Dow Jones Newswires
Shares in Tokyo Electric Power, the embattled operator of a stricken nuclear power plant, surged Wednesday on a report other Japanese power companies may be asked to share its compensation burden.
TEPCO shares closed up 11.55 percent at 502 yen after the Yomiuri Shimbun reported the utility's liabilities would be limited to 2-3.8 trillion yen ($23-$45 billion).
Shares in TEPCO plunged to historic lows last week on doubts about the firm's ability to manage the crisis at its Fukushima Daiichi nuclear plant, the worst atomic accident since Chernobyl in 1986.
Japan cut its assessment of the economy for the first time in six months after the devastating March 11 earthquake-tsunami and the nuclear crisis triggered by the disasters, the government said Wednesday.
"The economy was picking up, but it has shown weak signs recently due to the impact of the Great East Japan Earthquake," the Cabinet Office said in its monthly report. “It remains in a severe condition”.
The twin tragedy devastated infrastructure and manufacturing facilities in northeastern Japan, plunging the nation into its worst crisis since World War II, with fears over a stricken nuclear plant adding to uncertainty.
Analysts said the next focus will be on JPMorgan Chase's earnings and the US Federal Reserve's “Beige Book” report.