TOKYO -- Japan's prime minister met for the first time with leaders of weekly anti-nuclear protests Wednesday but rejected their demand that two recently restarted nuclear plants should be shut again.

Tens of thousands of people have been gathering every Friday night outside Prime Minister Yoshihiko Noda's office compound to protest against nuclear power because of safety concerns set off by last year's Fukushima Dai-ichi nuclear crisis.

The 11 protest leaders were allowed into the complex for the first time since they started chanting anti-nuclear slogans outside the tightly guarded building in April.

"When the majority of the general public opposed the restart, you forced it by trampling down on us. It was ridiculous and outrageous," protester Misao Redwolf told Noda as she sat across from him during the 30-minute meeting. "We will continue our protests as long as you keep ignoring our voices."

The protesters said meeting the prime minister was not their goal and they would continue to gather until their demands are met.

Noda initially called the demonstrations outside his office complex "big noise," triggering criticism. He promised the protesters on Wednesday that he would listen to people's views and reflect them in policy decisions.

But Noda did not accept their demands that his government shut down two reactors that were restarted in July and keep the rest of the country's 48 reactors shuttered.

He has repeatedly insisted that nuclear plants need to be restarted to avoid power shortages that would impact Japan's economy.

"I will carefully listen to your voices and in the end we will make a responsible decision as the government and choose an energy mix that is safe and reliable for the people," Noda said, wrapping up the talks.

Wednesday's meeting came four months after the anti-nuclear coalition requested one with Noda.

The protests started with dozens of people in April and have become mass demonstrations. The protesters say their peak turnout was as many as 200,000 people from around the country, while unofficial police estimates cited by media say 10,000 to 20,000 gather weekly.

Police provide extremely tight security. They fence off the crowd, effectively confining protesters to sidewalks and preventing them from forcing their way into Noda's official residence.

Japan required new safety checks on nuclear plants after the March 11, 2011, tsunami caused meltdowns at three reactors in Fukushima. All of Japan's 50 reactors went off line in May for maintenance and inspections, and only the two Ohi reactors in western Japan have resumed generating power.

The government is currently finalizing a mid- to long-term energy policy, deciding one out of three options of nuclear energy dependency by 2030 -- none, 15 per cent or 20-25 per cent. Officials initially had planned to pick a 15 per cent scenario, but after town meetings and analyzing initial responses of public comments, they are now considering a zero-per cent option.