A nuclear reactor in western Japan began full operations Monday, the first restart since the country shut down its atomic stations in the wake of last year's crisis at the Fukushima Daiichi plant.

Kansai Electric Power Co. (KEPCO), operator of the Oi power plant in the nation's industrial heartland, said its Unit No. 3 had come back to full capacity early Monday after the reactor was switched on earlier this month.

"The reactor has already shifted to a stable output mode without any trouble," a KEPCO spokesman said, adding that the utility plans to resume operations at another reactor in the same plant later this month.

The return to full operations ended a nearly two-month hiatus in the aftermath of the atomic crisis, but comes amid strong anti-nuclear sentiment in Japan which has seen protesters come out in their tens of thousands.

It also comes less than a week after a damning parliamentary report said the accident was a man-made disaster, marked by a lack of oversight and collusion between plant operator Tokyo Electric Power, the government and regulators.

On Sunday, the governor of southern Kagoshima prefecture, who supports the restart, handily won a new term even as the issue divides Japan with strong voices of opposition hanging over the controversial move.

Nuclear restarts were put on hold as the government mulled its options following the 9.0-magnitude earthquake and tsunami last year that crippled reactor cooling systems at Fukushima.

But in mid-June, Japan's Prime Minister Yoshihiko Noda gave the green light to restart two reactors at the Oi plant in Fukui prefecture, amid concerns about looming power shortages this summer.

Japan had been operating without nuclear power since early May when the last of its 50 working reactors was shut down for a scheduled safety check.

The nation turned to pricey fossil-fuel alternatives to fill the gap left by the shutdown of atomic plants which had supplied about one-third of resource-poor Japan's energy.

The government has asked business and households to cut back on their power usage by as much as 15 percent from summer levels two years ago, with the Oi restart expected to ease KEPCO's power shortfall.