In another blow for Tokyo Gov. Yuriko Koike's Kibo no To (Party of Hope), more than half of the Democratic Party's 47 Upper House members have ruled out joining the upstart party after the Oct. 22 Lower House poll, the DP's Upper House caucus chief said Friday.

Toshio Ogawa, speaking to reporters in Fujimino, Saitama Prefecture, said that he has already contacted many caucus members and found that over half of the 47 are not interested in changing sides and joining Kibo no To.

DP President Seiji Maehara, who effectively disbanded the party's Lower House caucus last month, delivered an ultimatum to Diet members in the chamber to link up with Kibo no To or run on an independent ticket. He also urged Upper House members to eventually join Kibo no To after the Oct. 22 vote.