South Korea's opposition vows to impeach interim president

South Korea's opposition has said it would impeach acting president Han Duck-soo in protest at the interim leader's refusal to sign into law special bills to investigate his impeached predecessor.

The main opposition Democratic Party had set Christmas Eve as the deadline for Han to promulgate two special bills investigating suspended President Yoon Suk Yeol's short-lived imposition of martial law and graft allegations surrounding his wife, Kim Keon Hee.

Parliament stripped the conservative leader of his duties on December 14 following his brief declaration of martial law 11 days earlier, which plunged the country into its worst political crisis in decades.

But Han, who stepped in to replace Yoon, rejected the opposition's demand at a cabinet meeting on Tuesday, insisting on bipartisan agreements for the two bills.

Impeachment proceedings

Han's stance "left us no other option but to interpret it as his intention to continue the insurrection by delaying proceedings", opposition floor leader Park Chan-dae told a press briefing.

"We will immediately initiate impeachment proceedings against Han."

The warning came 10 days after Yoon was impeached in an opposition-led vote, suspending him from presidential duties pending a Constitutional Court ruling on whether to uphold the decision.

The opposition is seeking two special independent investigative bodies to look into Yoon's martial law declaration and the controversial affairs of First Lady Kim, including alleged bribery.

Yoon is currently under investigation by a joint team comprising police, the defence ministry, and anti-corruption investigators.

The opposition says it needs only a simple majority in the 300-member parliament to impeach Han, as this is the threshold for a cabinet member.

The ruling People Power Party, however, argues that a two-thirds majority is required since Han is currently serving as acting president.