Japan nuclear companies apply to restart 10 reactors
Nuclear operators in Japan have applied to restart 10 reactors, potentially paving the way for a widespread return to nuclear power in coming years.
The four companies applied under new rules introduced following Japan's Fukushima nuclear disaster in 2011.
Japan's Nuclear Regulation Authority (NRA) says it will take at least six months to review each reactor.
All but two reactors have been offline since the earthquake and tsunami which crippled the Fukushima plant.
Hokkaido Electric, Kansai Electric, Shikoku Electric and Kyushu Electric submitted applications to restart the plants under the new regulations on Monday. They sent applications for a total of 10 reactors at five plants.
The new rules require nuclear operators to put in place better safeguards against disasters including tsunamis, earthquakes and terrorist attacks.
NRA chairman Shunichi Tanaka said that bringing safety standards to international norms would "take a long time".
The NRA is responsible for determining whether the reactors meet the new safety standards.
The nuclear companies are then required to seek approval from national and regional politicians.
"It is important that assessment will be done in a strict manner by the Nuclear Regulation Authority based on the new standards," Katsunobu Kato, deputy chief cabinet secretary, said.
"It is a precondition that host communities agree on the re-firing," he added.
Prime Minister Shinzo Abe wants Japan's nuclear reactors to be restarted. The country relied heavily on nuclear power for its energy supply prior to the 2011 disaster.
However, many in Japan are opposed to restarting the reactors.
The earthquake and tsunami on 11 March 2011 crippled the Fukushima Daiichi nuclear power plant, causing meltdowns at three nuclear reactors.
Engineers have since stabilised the plant but years of work lie ahead to fully contain the disaster and tackle its effects.