By Josh Smith and Ju-min Park
SEOUL (Reuters) - A defiant South Korean President Yoon Suk Yeol faces a second impeachment vote on Saturday over his short-lived attempt to impose martial law, a move that shocked the country, split his party and imperilled his presidency half way through his term.
Yoon rescinded his Dec. 3 move to impose military rule barely six hours later, after the opposition-controlled parliament defied troops and police to vote against the decree. But it plunged the country into a constitutional crisis and triggered widespread calls for him to step down on the grounds that he had broken the law.
Opposition parties plan to hold an impeachment vote at 4 p.m. (0700 GMT), with large demonstrations planned ahead of the vote.
Yoon's conservative People Power Party boycotted the first impeachment vote a week earlier, preventing a quorum.
Since then, PPP leader Han Dong-hoon has urged party members to vote for impeachment this time, and at least seven PPP members have said they would vote to impeach.
The opposition parties need at least eight PPP votes to impeach Yoon, as they control 192 of the 300 seats in the single-chamber parliament and impeachment requires a two-thirds majority.
Ahn Cheol-soo, a PPP lawmaker backing Yoon's impeachment, said in a Facebook (NASDAQ:META) post on Saturday that he would vote for impeachment "for the sake of swift stabilization of people's livelihood, economy and diplomacy".
The PPP floor leader said on Friday, however, that the party's stance remained to oppose impeachment.
PPP lawmakers were meeting Saturday morning to decide whether to change that position.
The main opposition Democratic Party said on Saturday Yoon's "madness" could no longer be tolerated.
"Refusing impeachment is treason against the people," the party said in a statement, asking more from the ruling party to join the impeachment.
'FIGHT TO THE END'
If impeached, Yoon would lose authority but remain in office until the Constitutional Court either removes or reinstates him. In the meantime, Prime Minister Han Duck-soo would serve as acting president.
If the court removes Yoon or he resigns, a presidential election must be held within 60 days.
Yoon is separately under criminal investigation for alleged insurrection over the martial law declaration and authorities have banned him from travelling overseas.
He has not signalled a willingness to resign and in a speech on Thursday vowed he would "fight to the end", defending his martial law decree as necessary to overcome political deadlock and protect the country from domestic politicians who he said were undermining democracy.
Yoon, president of Asia's fourth-largest economy, hopes political allies will rally to support him, but the fiery remarks appeared to find mixed reception among PPP lawmakers.
A Gallup Korea poll on Friday found two-thirds of supporters of Yoon's party opposing the impeachment, though three-quarters of all respondents supported it.
Protesters calling for Yoon's impeachment began gathering near the parliament on Saturday, while pro-Yoon right-wing rallies at the centre of Seoul were due to start early in the afternoon.
Some K-pop celebrities have slammed the president and plan to donate food and drinks for those participating in the rally to demand Yoon's impeachment.
People have been using delivery apps to pre-order food and coffee for protesters.
Elected in 2022, Yoon was widely welcomed in Washington and other Western capitals for his rhetoric defending global democracy and freedom, but critics said that masked growing problems at home.
He clashed with opposition lawmakers whom he has labelled as "anti-state forces", and press freedom organisations have criticised his heavy-handed approach to media coverage that he deems negative.
The crisis and ensuing uncertainty have shaken financial markets and threatened to undermine South Korea's reputation as a stable, democratic success story.
South Korean shares rose for a fourth straight session on Friday on hopes that the political uncertainty would ease after this weekend's parliamentary impeachment vote.