South Korea's President Yoon Suk Yeol addressed the nation on Saturday ahead of a vote in parliament to impeach him.

It was the first time he appeared before the public since plunging the country into political chaos four days earlier.

"I am truly sorry and would like to sincerely apologize to the people who were shocked," Yoon said. "I leave it up to my party to take steps to stabilize the political situation in future, including the issue of my term in office."

He added that there will be no second martial law order.

"There are rumors that martial law will be invoked again. Let me be clear. There will never be anything like a second martial law," Yoon said in an address to the nation.

Yoon also said he would not shirk his legal responsibility over the incident.

Ruling party head says Yoon must resign

Meanwhile, South Korea's ruling party leader Han Dong-hoon said an early resignation for Yoon was unavoidable because he is no longer able to carry out public duties.

"The normal performance of the president's duties is impossible under the (current) circumstances, and an early resignation of the president is inevitable," Han told reporters.

Lawmakers in South Korea were set to vote later Saturday on whether to impeach Yoon over his short-lived attempt to impose martial law, as protests calling for his removal grew nationwide.

Opposition says Yoon is 'dangerous'

South Korea's main opposition leader Lee Jae-myung said he will work hard to end Yoon's term early because it is "dangerous" for him to remain in the political sphere.

The impeachment of Yoon would require the support of 200 of the 300 members of the National Assembly. The opposition parties that jointly submitted the impeachment motion have a combined total of 192 seats.

That means they would need at least eight votes from Yoon's People's Power Party, which has 108 seats. One PPP lawmaker has already publicly stated that he will vote with the opposition.

A successful vote would suspend Yoon from office pending a ruling by the Constitutional Court.

Prosecutors, police, and the Corruption Investigation Office for High-ranking Officials have all launched investigations into Yoon and senior officials involved in the martial law decree.

dh/zc (AP, AFP, Reuters)