Finance Minister Choi Sang-mok became on Friday South Korea's second acting president in two weeks, as lawmakers voted to impeach the current acting leader, Prime Minister Han Duck-soo, fuelling political uncertainty in Asia's fourth-largest economy.

Investigators failed to take Yoon Suk Yeol into custody following a standoff with the presidential security service last week.

The president was suspended from his duties last month following a failed bid to impose martial law and his subsequent impeachment by parliament on December 14. Law enforcement authorities are seeking Yoon’s arrest as part of an investigation into alleged treason and abuse of power.

Both supporters and protesters staged rallies near the residence of South Korea's impeached President Yoon Suk-yeol on Sunday, a day before an arrest warrant for him expires. On the day, conservative groups supporting Yoon and labor groups which hold opposing views called on the public to gather outside the presidential residence.