KYODO NEWS - Shigeru Ishiba was formally reelected as Japan's prime minister on Monday after a rare runoff vote in parliament that his ruling coalition no longer controls, setting the stage for a minority government that may push him to yield more to an emboldened opposition bloc.

In the first runoff vote in three decades to select a new prime minister, Ishiba, who heads the Liberal Democratic Party, defeated his rival Yoshihiko Noda, leader of the main opposition party, the Constitutional Democratic Party of Japan, at the opening of a four-day parliamentary session.

None of the candidates secured 233 votes in the 465-member House of Representatives in the initial round -- a majority threshold required to be elected prime minister. After Ishiba received 221 votes, more than the 160 votes for Noda, the LDP chief was declared the winner.

Earlier in the day, Ishiba was elected prime minister in the House of Councillors, which is controlled by the LDP and the Komeito party. The prime minister will form a new Cabinet later Monday.

The prospect of a minority government means the ruling coalition needs to heed more to demands from the opposition bloc that has gained strength since the Oct. 27 general election.

The CDPJ has an increased presence in the lower chamber, and the same goes for the opposition Democratic Party for the People, which has been courted by both sides of the aisle, with its seats quadrupling from before the election.

DPP members confirmed shortly before the session that they would vote for the party's leader, Yuichiro Tamaki, although a magazine report exposing his alleged extramarital affair has added a layer of uncertainty at the last minute. He admitted the report was mostly accurate.

In the run-up to the parliamentary session, the ruling coalition signaled its willingness to work with the DPP and coordinate their policies, a critical step toward ensuring a stable government.

Ishiba held separate talks with Tamaki and Noda before the opening of the parliamentary session.

"I will take a sincere approach to all parties," Ishiba told reporters. "The important point is to make sure that Japan is a peaceful nation and people's livelihoods improve. We are on the same page on this with the DPP and the CDPJ."

The opposition camp is expected to ramp up pressure on Ishiba to push for drastic political reforms, as the LDP's defeat in the election was partly attributed to its failure to restore voter trust following the ruling party's inappropriate handling of political funds.

Ishiba, who took office in October, is expected to make minor changes to the lineup of his Cabinet this time, mostly replacing those who lost their seats in the election.

Former senior vice foreign minister Keisuke Suzuki will be named the country's new justice minister, and Taku Eto will again serve as farm minister. Hiromasa Nakano, a Komeito lawmaker, will assume the post of land minister in place of Tetsuo Saito, who became the party's chief.