The small opposition Social Democratic Party, once the key rival of the ruling Liberal Democratic Party, is struggling to hold on to its status as a force to be reckoned with in Japanese politics.

Since early December, the SDP had been discussing an integration proposal made by the main opposition Constitutional Democratic Party of Japan, part of a bid to form a viable political force against the ruling coalition of the LDP and junior partner Komeito. But the SPD has decided to delay a final decision.

Under a new leader to be elected later this month, the SDP will need to come up with other ways to regain its footing while discussing the merger proposal further.

SDP Secretary-General Hajime Yoshikawa told a news conference on Jan. 30 that the party has postponed the plan to decide whether to go ahead with the merger with the CDP at the party convention slated for Feb. 22-23.

The move followed a party meeting on Jan. 29, when local representatives cautioned against a hasty integration. The representatives claimed that they had not been given enough information on the future of the local organizations and civic movements they support.

On Dec. 6, CDP leader Yukio Edano proposed the merger to SDP chief Seiji Mataichi, as well as to Yuichiro Tamaki, leader of the Democratic Party for the People. After some talks, Edano and Tamaki could only decide to continue negotiations.

Initially, some SDP executives were positive toward the envisaged integration since it might stop the continuing decline in the number of party members in the Diet. But for many, that outlook changed.

“The failure of merger talks between the CDP and the DPP had a huge influence on our decision that we should not rush into a conclusion,” and SDP source said.

“Whether we merge or not, our current aim is to field candidates for the next House of Representatives election and win five seats as well as get 3 percent of all votes,” Mataichi said. He also expects the new party leader to manage the party with a vision for the future.

Under the nation’s election law, the SDP will lose its status as a political party unless it has at least five members in the Diet or gets 2 percent or more of votes in the most recent election for either the Lower House or Upper House.