Former prime ministers Junichiro Koizumi and Morihiro Hosokawa on Thursday visited the northern Japanese city of Hakodate in response to it filing a lawsuit to suspend the construction of a nearby nuclear power plant.

The two former prime ministers, who have become stern anti-nuclear campaigners following the 2011 Fukushima meltdowns, met with Hakodate Mayor Toshiki Kudo and observed through telescopes the construction site across the Tsugaru Straits of Electric Power Development Co.'s nuclear plant in Oma, Aomori Prefecture.

"We reaffirmed that Hakodate has the core problems of Japan's nuclear power issue," Koizumi told reporters after hearing from Kudo that the city would suffer in the event of a nuclear disaster.

The meeting "further motivated" Koizumi to work toward abolishing nuclear power, he added. In April 2014, the Hokkaido city filed a lawsuit with the Tokyo District Court against the state and the utility, commonly known as J-Power, to suspend construction of the Oma nuclear power plant. The case is still pending.

The lawsuit filed with the Tokyo District Court is a sign that municipalities at risk of being seriously affected by a nuclear crisis want a greater say in safety matters.

Koizumi, who served as prime minister between 2001 and 2006, and Hosokawa, who was in power from 1993 to 1994, established an entity last year to promote renewable energy in the wake of nuclear disaster at Tokyo Electric Power Co.'s Fukushima No. 1 power plant triggered by major earthquake and tsunami in 2011.