South Korean President Yoon Suk-yeol is facing backlash after attempting to impose martial law. Lawmakers filed a formal motion of impeachment to parliament at around 1 a.m. on Thursday.

The motion was submitted on Wednesday afternoon by the main opposition Democratic Party and five other parties. It accuses Yoon of violating the constitution and betraying the people.

During the plenary session, South Korean lawmaker Kim Seung-won said the president has "committed an unforgivable sin."

South Koreans were thrust into uncertainty on Tuesday after Yoon announced he would impose martial law. In a television address, he said it was necessary to defend the country from what he called ''pro-North Korean anti-state forces.'' He did not cite any specific threats.

The decision was reversed hours later after lawmakers voted it down. Yoon has not been seen in public since lifting the decree.

Under South Korea's impeachment rules, the motion will be put to a vote between 24 and 72 hours, which means lawmakers could act as early as Friday.

Yoon's ruling People Power Party said it will vote against the motion. The opposition lacks the votes needed for it to pass, which requires the approval of at least two-thirds of the assembly.

If the bill is passed, Yoon will be temporarily suspended from his duties.