South Korea's National Assembly Speaker, Woo Won-shik, has vowed in parliament that he and other MPs will fight to prevent martial law if President Yoon Suk Yeol declares it again.
South Korea's main opposition Democratic Party earlier said members of parliament were on stand-by after receiving many reports of another martial law declaration.
South Korea's Acting Defence Minister, Kim Seon-ho, then apologised for the concerns caused by the president's martial law declaration earlier this week and said that reports of another martial law declaration were not true.
Mr Kim said in a media briefing he would not obey any order to implement another declaration of martial law.
The ruling party's chief on Friday called for the "swift suspension" of duties of beleaguered President Yoon Suk Yeol, claiming he ordered the arrest of prominent politicians during the controversial imposition of martial law this week.
The comments by People Power Party leader Han Dong-hoon suggest that his party will change its earlier opposition to the impeachment of Mr Yoon over the crisis.
They came as South Korean prosecutors decided to conduct a joint investigation with military prosecutors into the emergency martial law declaration, according to a report by broadcaster YTN.
The main opposition Democratic Party and other small opposition parties submitted a joint motion to impeach Mr Yoon on Wednesday over his martial law declaration the previous night.
Martial law lasted about six hours, as the South Korean parliament — the National Assembly — quickly voted to overrule the president, forcing his cabinet to lift it early on Wednesday.
Mr Han stressed the need to suspend Mr Yoon's presidential power and responsibilities, saying he had received intelligence that Mr Yoon had attempted to use troops to arrest and detain major politicians during martial law.
The party chief said it was crucial that Mr Yoon's presidential duties were suspended swiftly, saying that the president posed a "significant risk of extreme actions, like reattempting to impose martial law, which could potentially put the Republic of Korea and its citizens in great danger".
Mr Han earlier said he would work to defeat the impeachment motion even though he criticised Mr Yoon's declaration as "unconstitutional".
He said there was a need to "prevent damage to citizens and supporters caused by unprepared chaos".
Impeaching the president would require support from two-thirds of the National Assembly, or 200 of its 300 members. The opposition parties together have 192 seats.
Parliament's rejection of martial law passed unanimously on Wednesday with support from 18 PPP lawmakers who belong to an anti-Yoon faction in the party.
If Mr Yoon is impeached, he would be suspended until the country's Constitutional Court rules on whether to remove him from office or restore his presidential power.
Prime Minister Han Duck-soo would take over presidential responsibilities.
Following this week's crisis, Mr Yoon's presidential approval rating has plunged to a new low of 13 per cent, according to a Gallup Korea poll released today.
AP/Reuters
