South Korea’s parliament on Thursday formally moved to impeach President Yoon Suk Yeol over a failed attempt to impose martial law, but his party vowed to oppose the move, throwing the process into doubt.

Lawmakers could vote for the bill as early as Friday, but Yoon’s ruling People Power Party said it would reject it. The opposition Democratic Party, which has a majority in parliament, needs at least eight members of the ruling party to support the bill in order to pass the law.

“The Yoon Suk Yeol regime’s declaration of a state of emergency under martial law caused great confusion and fear among our people,” Democratic Party lawmaker Kim Seung-won said at a late-night session of South Korea’s National Assembly in the early hours of Tuesday Thursdays. None of the 108 members of the ruling party were present when the motion was introduced.

“We must revoke President Yoon’s authority immediately. He committed an indelible, historic crime against the people whose fears must be alleviated so that they can return to their everyday lives,” Kim said.

If the impeachment motion is approved and confirmed by the Constitutional Court, Yoon would be the second South Korean president to be impeached since massive candlelight protests over an influence-peddling scandal led to the ouster of former President Park Geun-hye in 2017.

By declaring martial law late Tuesday, Yoon sought to ban political activity and censor the media in South Korea, which has Asia’s fourth-largest economy and is a key U.S. ally. The shock move divided Yoon’s minister and his ruling People Power Party and triggered six hours of political chaos.

Armed troops entered the National Assembly building in Seoul but held off as parliamentary staff fired fire extinguishers at them. Lawmakers rejected the martial law decision while protesters scuffled with police outside.

Protesters held candlelight vigils in Seoul late Wednesday, demanding Yoon’s resignation.

The impeachment motion against Yoon was presented to a plenary session that began shortly after midnight Thursday, paving the way for an impeachment vote in the following 24 to 72 hours.

Opposition parties need a two-thirds majority to pass the law and the support of about eight members of Yoon’s own party to get the necessary 200 votes to impeach him. If the bill is approved, South Korea’s Constitutional Court will decide whether to grant the request – a process that could take up to 180 days.

If Yoon is suspended from exercising power due to Parliament’s passage of the law, Prime Minister Han Duck-soo would step in as chairman.

If the embattled president resigns or is removed from office, a new election would take place within 60 days.