Despite fundamental differences in policy and continued doubts about how voters would react, Osaka Mayor and Nippon Ishin no Kai (Japan Restoration Party) head Toru Hashimoto has indicated a tieup with former Tokyo Gov. Shintaro Ishihara might occur.

"I can't exclude the possibility" of a tieup, he told reporters Wednesday. Top Ishin no Kai officials and those from Tachiagare Nippon (Sunrise Party), which will form the core of Ishihara's party, are scheduled to meet Friday in Tokyo to try to work out an agreement.

Hashimoto's decision to consider a tieup with Ishihara's new party came after intense arguments between him and top party leaders, party officials said. Hashimoto has long insisted Tachiagare Nippon's policies are too different from Ishin no Kai for a tieup to work, and that he preferred a personal alliance with Ishihara in order to take advantage of his popularity.

However, Osaka Gov. Ichiro Matsui, who is Ishin no Kai's secretary general, and other party members, many of them former Liberal Democratic Party members who knew Tachiagare Nippon head Takeo Hiranuma when he was in the LDP, are more willing to work with him.

In recent weeks, as Nippon Ishin no Kai's initial popularity has waned, Matsui has quietly assumed a more influential role in the decision-making process.

Friday's meeting is expected to focus on a number of areas, including nuclear power, the Trans-Pacific Partnership free-trade agreement, and revising the Constitution. While Ishin no Kai's stated policy platform is fundamentally different from the views expressed by Ishihara and Hiranuma, Matsui and other Ishin no Kai members have personal views on these and other issues more in line with Tachiagare Nippon, leaving open the possibility of some sort of agreement.