Concerns about Japan's summer energy demand and the impact on the economy factored into decision, which many see as a victory for the powerful nuclear energy industry.
Japan on Saturday approved the resumption of nuclear power operations at two reactors despite mass public opposition, the first to come back on line after they were all shut down following the Fukushima crisis.
Prime Minister Yoshihiko Noda, his popularity ratings sagging, had backed the restarts for some time. He announced the government's decision at a meeting with key ministers, giving the go-ahead to two reactors operated by Kansai Electric Power Co at Ohi in western Japan.
The decision, despite public concerns over safety after the big earthquake and tsunami crippled the Fukushima plant, could open the door to more restarts among Japan's 50 nuclear power reactors.
"There is no such thing as a perfect score when it comes to disaster prevention steps," Trade Minister Yukio Edano told a news conference after the announcement.
"But, based on what we learned from the Fukushima accident, those measures that need to be taken urgently have been addressed, and the level of safety has been considerably enhanced (at the Ohi plant)," he said.
Edano, who holds the energy portfolio, said the government policy to reduce Japan's dependence on nuclear energy in the medium- to long-term was unchanged despite the decision.
The decision is a victory for Japan's still-powerful nuclear industry and reflects Noda's concerns about damage to the economy if atomic energy is abandoned following the world's worst nuclear disaster since Chernobyl.