Amid widespread criticisms and protests, Japan will allow, starting next month, some of its nuclear facilities to resume operation, about 15 months after the nuclear accident at the Fukushima Daiichi nuclear power plant.

The No. 3 reactor at Oi plant in western Japan's Fukui Prefecture is expected to reach full capacity in early July, while the No. 4 reactor at the same facility will be back on line in the same month.

The two reactors have been shut down along with all of Japan's 50 nuclear reactors, following a magnitude 9.0 earthquake and tsunami in March last year that saw the collapse of the nuclear plant in Fukushima prefecture and that led to one of the world's worst-ever atomic disasters.

The crisis also caused radiation leaks into the environment and has endangered the lives of thousands of people in the surrounding areas.

The decision to resume using nuclear power has been met with demonstrations and protests in Japan.

On Saturday, thousands of protesters rallied in Tokyo and Osaka to oppose the move. Several other protest marches were scheduled in other parts of the country.

Surveys showed that more than half of the Japanese people are against the nuclear power, but a power shortage this summer has prompted the government to restart the reactors.

Before the Fukushima nuclear accident, about 30 percent of Japan's energy requirements were supplied by nuclear reactors.

Critics here claimed that the government has come up with the decision to restart some nuclear plants even before a new energy policy has been laid out. A new bill on the use of nuclear energy, which is due next month, is expected to take a harder line on nuclear energy, with some even speculating that the authorities might choose to abandon nuclear power altogether.

The cabinet led by former Prime Minister Naoto Kan had vowed on several occasions to reduce the nation's reliance on nuclear energy, but the current government's stance on the issue has been ambiguous.

To make the situation complicated, the decision to resume the generation of nuclear power also came before the formation of a new nuclear regulator, which is expected to be launched in September.

The current regulators are the much-criticized Nuclear and Industrial Safety Agency under the Trade Ministry and an oversight commission under the Cabinet.

Many local authorities said that a new agency should first be created as a prerequisite for the resumption of the nuclear reactors' operations.

"Definitely I am opposed to the restart (of nuclear reactors)," a resident in Tokyo surnamed Nakagawa told Xinhua. "I have been deeply worried about the radiation leaks and their impact on health after the Fukushima accident," she added.

The residents living around the Oi plant have also expressed concerns about what could happen to them in the event of another nuclear accident.

Critics said proper evacuation procedures have not been worked out for the communities surrounding the facility.

With so many questions being left unanswered, the Japanese government needs to weigh the restart of nuclear power to solve energy shortage against the real concerns of its people, some critics said.

Nakagawa and her family moved into an apartment equipped with solar power to counter possible power cut. Promoting green and renewable energy may take time, but Nakagawa's practice should give the Japanese government food for thought.