Osaka Mayor Toru Hashimoto, who heads Nippon Ishin no Kai (Japan Restoration Party), said Tuesday he would not refuse tying up with three members of the Tokyo Metropolitan Assembly even though they supported a petition declaring the Constitution invalid.

Kazusa Noda, a former Liberal Democratic Party member, along with Hirofumi Yanagase and Zenko Kurishita, formerly of the Democratic Party of Japan, formed the group Tokyo Ishin no Kai last month and announced they were tying up with Osaka Ishin no Kai, Hashimoto's group for local politicians. They were also expected to join Nippon Ishin no Kai, an official national political party that currently has nine members in the Lower House.

The move came three months after they submitted a petition calling for the Tokyo assembly to recognize that the Constitution, officially adopted by the Diet in 1947, is not valid because it was promulgated when Japan was under the Allied Occupation.