Japan's government is aiming to restart a nuclear reactor by around June following a lengthy and politically-sensitive approval process in the wake of the Fukushima disaster, sources familiar with the plans said.

Prime Minister Shinzo Abe's government has been pushing to bring some of the country's reactors back online after all 48 closed following meltdowns at the Fukushima Daiichi plant in March 2011, arguing they are key to economic growth.

A reboot in what was once the third-biggest user of nuclear power would boost its utilities, which have been hit by huge losses as they switch to fossil fuels and upgrade nuclear plants, with two turning to the government for bailouts.

But the move would be controversial in a nation where most oppose nuclear power, with memories still fresh of the worst atomic crisis since Chernobyl in 1986.

"We urge the government to take into full consideration the tremendous suffering from the nuclear power plant accident and make sure that future policy ensures the safety and peace of mind of all citizens," Fukushima Governor Masao Uchibori said, when asked about restarts.

Kyushu Electric Power Co will be given the greenlight to restart two nuclear units in southwestern Japan, with June pencilled in for the first unit, according to three sources familiar with the government's thinking. They declined to be identified as they were not authorised to speak with media.

By June, Japan's Nuclear Regulatory Authority is expected to have completed the final checks and appraisal of the reactors at Kyushu Electric's Sendai station, letting Abe give the final go-ahead after local authority approval late last year.

A June restart would also mean local elections scheduled for April would be out of the way, giving the government some leeway to take such a potentially unpopular step.

An industry ministry spokesman said no announcement had been made on Sendai's restart date.

MOTHBALLED

A gradual return to nuclear would not immediately end Japan's heavy reliance on fossil fuel imports that has stoked a record trade deficit.

The use of fuel oil is likely the first to be curbed as it is the most expensive substitute and is being burned in older units that had been mothballed until being brought back online after Fukushima.

Demand for coal and liquefied natural gas, which has hit successive records as nuclear plants were shut down, will likely remain high, utilities and analysts have said.

Kyushu Electric's Sendai reactors, commissioned around 30 years ago, received initial safety clearance in September.

Two more rounds of checks are ongoing and, while there have been hitches, the June start date looks feasible for inspectors to finish their job, said another source.

However, there is a chance restarts could be delayed as the units have been shut for more than three years and may need further maintenance.

(dna)