SEOUL - The South Korean prosecution said the impeached president Yoon Suk-yeol on Sunday defied a summons in a martial law probe, and it planned to issue a second summons, Yonhap news agency reported.  

Yoon said in a televised address on Saturday that he will “not give up” after the National Assembly voted to impeach him over his botched martial law imposition earlier this month.

This developed as Kweon Seong-dong, the floor leader of the South Korean ruling party, said  that his party has rejected a proposal by the country's main opposition party to set up a consultative body to stabilize the operation of state affairs.

The People Power Party is still the ruling party and an acting president has already been appointed according to the Constitution, Kweon said at the National Assembly on Sunday.

Earlier in the day, Lee Jae-myung, leader of the main opposition Democratic Party, said in a press conference that it is imperative for the country to realize a speedy normalization as the national defense and security posture have been undermined by the "insurrection" incident, referring to the botched emergency martial law imposition by the now-impeached president Yoon.

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Lee called on the country's parliament and government to set up a consultative body to stabilize the operation of state affairs in the spirit of multi-party cooperation in governance. He also said that his party will not consider for now an impeachment against Prime Minister Han Duck-soo, the country's acting president.

Under the country's Constitution, the prime minister assumes the role of acting president if the president is impeached. Yoon's presidential duties are only suspended until the Constitutional Court delivers its ruling on the impeachment motion.

Lee stressed to Han the importance of managing state affairs in a neutral stance during their phone call on Saturday, the chief of the Democratic Party of Korea told reporters. Yoon has been suspended from his presidential duties since the National Assembly voted on Saturday to impeach him.

Han said he would do his best to stabilize state affairs in accordance with the Constitution and laws, vowing to leave no vacuum in the country's politics.

Han said the government would make every effort to minimize the impact on the daily lives of the people and establish a solid security posture.

He also vowed to ensure the smooth operation of financial and foreign exchange markets and maintain the trust of the international community, calling on public officials to work together to overcome the crisis.

Han speaks with Biden

Han also talked to US President Joe Biden in a phone call on Sunday, vowing to maintain and develop the alliance between the two countries, Yonhap news agency reported, citing Han's office.

The South Korean government "will carry out our diplomatic and security policies without disruption and work to ensure that the South Korea-US alliance continues to be maintained and developed without wavering," Han was quoted by Yonhap as saying during the phone conversation.

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He explained to the US president that all state affairs of South Korea will be run strictly in accordance with the constitution and laws.

Biden said the US side will continue to work together with the South Korean side for the development and strengthening of the US-South Korea alliance and US-Japan-South Korea cooperation, according to Yonhap.

'Swift, fair' trial

Moon Hyung-bae, the acting chief of the Constitutional Court, said he will convene a meeting of judges at 10 am local time Monday, vowing to conduct a "swift and fair" trial.

The court has also decided to pick two judges to oversee an examination of evidence and form a legal review task force consisting of constitutional researchers.

If the court upholds the impeachment, Yoon will be removed from office, and the prime minister will continue to act as president until a new president is elected within 60 days.

Meanwhile, prosecutors on Sunday sought an arrest warrant for the head of the Army Special Warfare Command over his role in Yoons short-lived imposition of emergency martial law, Yonhap news agency reported.

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The arrest warrant for Lt Gen Kwak Jong-keun was filed on charges of insurrection and abuse of power.

The military official is accused of sending troops to the National Assembly when the martial law was imposed on the night of Dec 3, and allegedly colluding with Yoon and former Defense Minister Kim Yong-hyun to incite a riot with the purpose of subverting the constitution, according to the report.

Kwak, already suspended from his duties, has been placed under a travel ban in connection with an investigation of Yoon's martial law declaration.