South Korean investigators said Wednesday they would execute an arrest warrant for Yoon Suk Yeol over his declaration of martial law by the deadline of January 6, as the impeached leader vowed to fight to the bitter end.

The arrest warrant for an incumbent president is unprecedented, and deepens the political crisis that has engulfed South Korea.

Lawmakers from South Korea’s opposition party are planning to vote on Friday to impeach Prime Minister and acting President Han Duck-soo. The country’s National Assembly already impeached and suspended President Yoon Suk Yeol earlier this month for imposing an unpopular martial law in the country.

South Korea's opposition Democratic Party submitted an impeachment motion against embattled acting President Han Duck-soo on Thursday in the latest challenge to the country's leadership structure.

The Seoul Western District Court on Tuesday issued an arrest warrant against President Yoon Suk Yeol. The arrest warrant request was filed by the Corruption Investigation Office for High-ranking Officials (CIO) a day earlier on Monday.