South Korean President Moon Jae-in speaks during a ceremony of the 103rd anniversary of the March First Independence Movement Day, the anniversary of the 1919 uprising against Japanese colonial rule, in Seoul, South Korea on March 1, 2022. (JEON HEON-KYUN / POOL PHOTO VIA AP)

SEOUL - The party of outgoing South Korea President Moon Jae-in scrambled to regroup on Friday as its leadership resigned in en masse after its devastating election defeat, but still holds enough seats to potentially thwart the new president's agenda.

Conservative opposition candidate Yoon Suk-yeol, a former prosecutor-general and political novice, won South Korea's closest election in decades on Wednesday, tapping voter disillusionment over spiralling housing prices, deepening inequality and scandals involving Moon's aides. 

Some of the Democrats called for soul searching and the need to shake off perceptions of arrogance, while others said the top priority should be placed on the June election of heads of local governments nationwide, not the leadership change

The governing Democratic Party's entire leadership team resigned on Thursday, taking responsibility for the result, leaving the party's 172 lawmakers and other officials to gather on Friday to analyse the failure and chart the way forward.

There were signs of discord among the Democrats.

Some called for soul searching and the need to shake off perceptions of arrogance, while others said the top priority should be placed on the June election of heads of local governments nationwide, not the leadership change.

Despite the defeat, the Democrats will retain their solid majority in the 300-seat, single chamber parliament until the next election in 2024, meaning their support is essential for Yoon to pass new legislation, approve budgets and appoint cabinet ministers.

"The government will change, but the power balance in parliament will not," said Shin Yul, a political science professor at Myongji University.

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"How Yoon would handle the lopsided structure would be key, and in order to draw the opposition's cooperation, he would need strong public support behind any policy drive."

South Korea’s president-elect Yoon Suk Yeol attends a ceremony to disband a presidential election camp at the National Assembly Library in Seoul, South Korea on March 10, 2022. (SONG KYUNG-SEOK / POOL PHOTO VIA AP)

Agenda in check

Yoon promised after his victory to heal polarized politics, embrace foes and work with the Democrats.

The Democrats are exploring how to keep Yoon Suk Yeol's conservative agenda in check, including his pledge to buy an additional THAAD US missile system, which Yoon's campaign estimated would cost up to 1.5 trillion won ($1.2 billion)

But the bruising campaign marred by scandals, smears and gaffes exposed some bitter feelings harboured by both sides, highlighting the challenges Yoon faces when he is sworn in May.

Before his resignation, the Democrat chairman said last week Yoon would be a "vegetative president" who would struggle to run the government with the ruling party occupying just 105 seats.

Yoon told a rally on Tuesday there was talk among some Democrats that if he was elected they would disrupt his government and rally dissenters in his party.

The Democrats are exploring how to keep Yoon's conservative agenda in check, including his pledge to buy an additional THAAD US missile system, which Yoon's campaign estimated would cost up to 1.5 trillion won. ($1.2 billion) 

Shin said an early test could be the local government election in June, and confirmation hearings when Yoon nominates cabinet ministers after taking office.

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Moon had been criticized for appointing the highest number of nominees without bipartisan approval in the country's democratic history.

"The ruling party had faced backlash after using its majority to press ahead with its agenda without consensus," Shin said. "They would know they still play a role in fostering bipartisan politics, with their power in parliament."