TOKYO, Oct. 20 (Xinhua) -- Japan's ruling and opposition parties have agreed to hold a parliamentary vote to pick a new prime minister to replace outgoing Shigeru Ishiba on Oct. 21 when an extraordinary Diet session kicks off.

With the withdrawal of long-time ally Komeito from the ruling coalition, it remained uncertain whether new ruling Liberal Democratic Party (LDP) leader Sanae Takaichi will be elected as prime minister.

POLITICAL MANEUVERING

Takaichi won the LDP presidential election on Oct. 4. For the new ruling party leader to become the prime minister, she must win the parliamentary vote. With the breakup of the LDP-Komeito coalition, major opposition parties have been holding frequent talks recently.

Leaders of three major opposition parties, the Constitutional Democratic Party of Japan, the Democratic Party for the People and the Japan Innovation Party, held talks on Wednesday.

The three parties hold a relatively large number of seats in the Diet, Japan's parliament. If they could unify to field a joint opposition candidate for the prime ministerial vote, they could potentially prevent Takaichi from becoming prime minister. However, the three parties failed to reach a policy consensus during the meeting.

Meanwhile, the Japan Innovation Party held policy discussions with the ruling LDP for two consecutive days on Thursday and Friday, with an eye toward forming a coalition.

The party's co-leader Fumitake Fujita told media on Friday that the consultations with the LDP "moved forward considerably" and they will make "final arrangements" toward an agreement on cooperation, adding that his party will end talks with the other two major opposition parties.

The largest opposition, the Constitutional Democratic Party of Japan, said Friday that in light of the Japan Innovation Party's decision, it is now considering having its members cast ballots for its leader Yoshihiko Noda in next week's prime ministerial vote.

UNCERTAINTIES REMAIN

The support of the Japan Innovation Party in the upcoming vote will greatly raise Takaichi's chances of being Japan's first female prime minister.

Currently, the LDP and the Japan Innovation Party have confirmed their common ground on basic policies, such as the Constitution amendment, foreign affairs and national security. However, there are significant differences in areas such as food consumption tax and political donations, making it unclear whether they could eventually form a ruling coalition.

On Friday, Co-representative of the Japan Innovation Party Hirofumi Yoshimura, who also serves as Osaka governor, said that his group will not form a coalition with the LDP unless they reach an agreement to specify parliamentary seat cuts by the end of the year, which is a "nonnegotiable condition."

LDP heavyweight Ichiro Aisawa said on social media that "self-sacrificing reforms do not mean slashing parliamentary seats," describing Yoshimura's plan as "out of the question," as the reduction could decrease the number of rural representatives.

POSSIBLE OUTCOMES

Judging the current situation, there are three possible outcomes for the prime ministerial vote.

The first scenario involves the LDP and the Japan Innovation Party forming a ruling coalition, with Takaichi elected as prime minister. In this case, the alliance does not hold a majority in either chamber of the Diet, leaving a minority government and potentially significant challenges of implementing policies.

In the second scenario, the LDP governs alone with Takaichi becoming prime minister. If the opposition fails to field a unified candidate, even without an alliance with the Japan Innovation Party, Takaichi could still win by leveraging the LDP's dominance in the Diet with the largest number of seats. However, the lack of political alliances would make governing more difficult.

The third scenario, the least possible one, is that opposition parties successfully form an alliance and win the vote. At present, the total number of seats held by center-left parties could be less than that of the LDP. If an opposition alliance is formed, it would likely include right-leaning parties. In this case, even if the opposition alliance wins the vote, considerable challenges will remain due to significant policy differences within the coalition.