Japan's Prime Minister Naoto Kan on Friday pledged a "revolutionary" shift away from atomic power and towards renewable energy in the wake of the Fukushima nuclear disaster.
His cabinet also agreed on a plan to rebuild after the quake and tsunami disaster of March 11, saying reconstruction would cost around 19 trillion yen ($245 billion) over the next five years.
The embattled premier, who has been fighting calls to resign amid rock-bottom poll ratings, was speaking as a government panel said it would spend the rest of the year working on a new energy strategy.
"We have made a significant decision on energy policy, including nuclear power," Kan said in a televised press conference.
"As a medium-term revolutionary energy and environmental strategy, we have decided to start a thorough review of nuclear power policy and draw a roadmap for a reduction of the dependence on nuclear power.
"The Japanese government will aim for a society that does not depend on nuclear power and reduce its dependence on nuclear power in a planned and step-by-step manner."
Earlier Friday the national policy minister, Koichiro Gemba, assigned by Kan to draft a plan to reduce atomic energy use, said the government would spend a year drafting a new "roadmap" on energy policy.
"It will require nationwide discussion," Gemba told a briefing. "Our basic stance is to reduce (nuclear power) while thoroughly improving its safety."
Kan, a one-time environmental activist, has pledged to boost alternative energy sources to 20 percent of the nation's energy mix by the 2020s. They currently make up about nine percent, most of it hydroelectric power.
Gemba, who heads the Kan cabinet's Energy and Environment Council, said the envisioned roadmap the panel was drafting will set immediate goals to secure a stable energy supply amid post-disaster power shortages.
Medium-term goals until 2020 should include decentralised energy systems, with reduced nuclear use, he said. The long-range target for 2050, he said, was the "best energy mix" that would use new technologies.
The government will promote private investment in renewable energy in regional areas, as well as advances in energy savings and efficiency, which "will create sources of economic growth," Gemba said.
It would also aim to reduce the dominance of Japan's regional power companies and consider withdrawing their responsibility for operation of electricity transmission grids.
In addition, the government would set up a panel to reassess the total cost of atomic power, factoring in the compensation likely to be paid to evacuees and other victims of the Fukushima accident, he said.
Japan until the March 11 disaster relied on nuclear power for about 30 percent of its energy needs and had planned to boost that to 50 percent by 2030, but Kan has since called for a review "from scratch" of that plan.
More than four months since the quake and tsunami sparked the ongoing Fukushima nuclear disaster, only 16 of Japan's 54 reactors are operational, with most of the closed plants now undergoing safety checks.
More nuclear plants are due to go offline for regular checks and maintenance in coming months, while many regional governments that host atomic power stations have been unwilling to approve reactor restarts.
If Japan switches off all its nuclear plants, it will face a roughly 10 percent shortage of energy next summer, particularly in Tokyo and surrounding areas, and risks higher electricity bills, the panel said.
A recent poll found 70 percent of people expressed full or qualified support for Kan's call for a society that does not rely on nuclear power.
The survey also found that public support for the Kan cabinet had fallen to 17 percent, the lowest level since it took power a little over a year ago.