Tokyo Gov. Yuriko Koike's new national party, increasingly seen as representing a challenge to the ruling coalition, is unlikely to win enough seats in the Oct. 22 general election to seize power, a top party official said Sunday.

Masaru Wakasa, a founding member of Kibo no To (Party of Hope), also said Koike is not expected to quit her post as governor and run for a Lower House seat herself "as long as she is looking to secure enough seats to put us in a position to take power in the next election" after this one.

The former prosecutor also said Kibo no To may not be able to field the 233 candidates needed to capture a simple majority in the 465-seat Lower House.