Activists and protesters gather at the regulatory commission's office building in Tokyo, July 16, 2014. [Photo/IC]

TOKYO - A nuclear plant in southern Japan cleared an initial safety hurdle on Wednesday which could make it the first nuclear facility to restart under tough new safety regulations after the industry was idled by the 2011 Fukushima disaster.

With Japan in its first summer without nuclear power in four decades, Prime Minister Shinzo Abe is pushing to restart the country's nuclear sector, as a prolonged shutdown forces the nation to rely on expensive fossil fuel imports.

The Nuclear Regulation Authority gave preliminary safety approval for Kyushu Electric Co's Sendai plant, accepting its upgraded design and safety features. The new safety standards involve safeguards against natural disasters, like earthquakes and tsunami, and severe nuclear accidents.

The nuclear station could restart this autumn, September-November, if it gains approval from the local communities.

"This is a step forward. After we get the safety decision we would like to move towards restarts with understanding from local (townships)," said Abe during a visit to northern Japan on Wednesday.

Japan's reactors were gradually taken offline, with the last one shutting down last year, after a massive earthquake and tsunami crashed into the Fukushima Daiichi plant in March 2011, triggering the worst nuclear disaster since Chernobyl in 1986.

The Fukushima disaster shook public confidence in atomic power and exposed close ties between the powerful nuclear industry and a regulator that was overseen by a government arm that promoted the energy source.

The NRA, an independent watchdog set up in 2012, has been vetting restart applications for plants for over a year.

Regulatory officials held 62 hearings and pored through thousands of pages of technical papers to assess upgraded safety features of the Sendai plant.

"I believe we were able to compile this review with independence and transparency while maintaining neutrality. I hope and wish that this (process) will be able to garner the public's trust, but that is for the public to decide," said NRA chairman Shunichi Tanaka.

Sendai's approval comes as a relief for Kyushu Electric, which has posted three years of losses and asked for a bailout by a state-backed bank. It expects to spend more than $3 billion to upgrade its two nuclear plants in southern Japan.

The NRA decision will also help the broader nuclear industry. The approval process for the five other plants with similar pressurised-water reactors will likely go more quickly, said NRA director Tomoya Ichimura. Nine of Japan's electric utilities have applied to restart 19 reactors.

Japan's nuclear regulator said on Wednesday that its assessment of Kansai Electric Power's Takahama nuclear plant in western Japan was moving along smoothly and was nearly complete on most issues.

A restart of the Sendai plant would be a boost for Abe.

The blackout of Japan's nuclear industry, which supplied about one-third of Japan's electricity before Fukushima, has led to rising electricity rates for residents and businesses and has contributed to a record string of 23 months of trade deficits.