Leader of Japan's Liberal Democratic Party (LDP) Shigeru Ishiba was reelected as the country's prime minister on Monday after securing the most votes in both houses of the Japanese Diet.

The Diet, or parliament, convened an extraordinary session on Monday afternoon to choose the prime minister. As the ruling coalition of the LDP and Komeito lost its long-held majority in the general election last month, the vote ran into a runoff between Ishiba and major opposition Constitutional Democratic Party leader Yoshihiko Noda.

In the runoff voting in the House of Representatives, 67-year-old Ishiba received 221 votes, outperforming Noda to become the country's 103rd prime minister despite falling short of the 233 majority threshold.

He will later be formally inaugurated at a ceremony at the Imperial Palace and hold a press conference in the evening.

Ishiba took office as the country's 102nd prime minister in early October and promptly called a snap election, aiming to solidify his position. But instead of a strengthened mandate, he faced a significant setback as voters, frustrated by rising inflation and a slush fund scandal, handed the ruling bloc its worst performance since 2009.

The LDP and Komeito got 215 of the 465 seats in the powerful chamber of parliament, below the 233 seats needed for the majority. The LDP alone won 191 seats, much less than the 247 seats it held before the election.

In contrast, the main opposition, the Constitutional Democratic Party, significantly increased its representation, rising from 98 seats before the election to 148 seats.