He denied the accusation but accepted some responsibility for the ensuing crisis by failing to dissuade Yoon from making the surprise move.

Here’s what you need to know.

Who is Han Duck-soo?

“It is my life’s honour that I have been able to serve the people with all my might,” Han said after parliament voted to impeach him.

The prime minister can also deliberate major national policies.

What political roles has Han Duck-soo held?

His roles have ranged from prime minister, finance minister and trade minister to presidential secretary for policy coordination, besides being ambassador to the United States and the OECD and heading up think tanks and organisations.

“He has served in key posts in state affairs solely through recognition of his skills and expertise, unrelated to political factions,” Yoon said when appointing Han in 2022, echoing descriptions used when previous administrations tapped him.

Yoon Suk Yeol was suspended from presidential duties after an impeachment vote on 14 December. Source: AFP / South Korean Presidential Office

Han has experience working with South Korea’s key ally the United States, having been deeply involved in the process of signing the US-South Korea Free Trade Agreement.

“He is a civil servant through and through, who didn’t take on a political colour despite working under (five presidents),” said a former high-ranking government official speaking on condition of anonymity.

What happens next for South Korea’s government?

If Yoon is removed, a presidential election must be held in 60 days. South Korea’s constitution does not say how much the acting president is empowered to do in the role.