Japan's nuclear watchdog on Wednesday gave the green light to restarting two more atomic reactors, days after pro-nuclear Prime Minister Shinzo Abe swept to election victory.

The Nuclear Regulation Authority (NRA) said it believed the two units at Takahama nuclear power plant in central Fukui prefecture met toughened safety standards introduced after the tsunami-sparked disaster at Fukushima in 2011.

The actual restarts, however, will be delayed until a month-long public consultation is held and local authorities give their blessing.

The NRA's nod -- its second, after granting approval for reactors at another site -- comes just three days after Abe received a fresh mandate from voters in Sunday's general election.

While the two-week campaign focused almost entirely on his economic blitz -- "Abenomics" -- the premier has insisted his other policies, including his plan to restart nuclear reactors, have been endorsed.

However, recent opinion polls showed about half of voters are against restarts, with 30-40 percent in favour.

Even so, Abe is expected use his new four-year mandate to push for nuclear power stations to get back online.

Once nuclear-dependent Japan is now highly sceptical of the technology. The national psyche is badly scarred by the disaster at Fukushima, where reactors went into meltdown after their cooling systems were swamped by a tsunami.

Tens of thousands of people were evacuated because of rising levels of radiation, with many still unable to return to their homes. Scientists warn that tracts of land may remain uninhabitable for decades.

Critics say the catastrophe at Fukushima was at least partially a man-made one, charging that a spineless regulator did nothing to unpick the close ties between powerful electricity generating companies and the government.

The NRA was launched as a watchdog with teeth and has shown willingness to take on the industry's vested interests.

But environmental campaign group Greenpeace said the NRA was failing in its duty and "ignoring major nuclear risks to the... region and public concerns".

The group said plant operator Kansai Electric Co.(KEPCO) does not have effective emergency plans in place for residents in and outside Fukui prefecture in the event of a serious accident.

KEPCO "is keen to restart its reactors, and the regulator is doing all it can to help them," it said.

In September, the NRA gave safety approval for the restarting of two reactors at the Sendai nuclear plant in western Japan.

Politicians there last month granted permission for the plant to go back online, and restarts are expected sometime next year after NRA-mandated remedial work is completed.