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Parliament to vote on Han's impeachment on Friday

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Han became interim leader after Yoon's impeachment

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Government in gravest political crisis in four decades

(Updates Dec 14 Newsmaker after Han threatened with

impeachment)

By Joyce Lee

SEOUL, Dec 26 (Reuters) - Prime Minister Han Duck-soo,

who became South Korea's acting president after Yoon Suk Yeol's

impeachment, is a career technocrat whose wide-ranging

experience and reputation for rationality may not be enough to

stem the country's deepening political crisis.

Since parliament's impeachment vote against Yoon passed on

Dec. 14 after his short-lived martial law declaration on Dec. 3,

Yoon has been suspended from exercising presidential powers and

the prime minister took over in an acting role.

In a country sharply divided by partisan rhetoric, Han has

been a rare official whose varied career transcended party

lines.

He has been facing the challenging task of keeping

government functioning through its gravest political crisis in

four decades, while also dealing with threats from nuclear-armed

neighbour North Korea, and a slowing economy at home.

However, his tenure as acting president may be cut short as

the main opposition Democratic Party, which controls parliament,

plans to vote to impeach Han as well on Friday over a battle on

Constitutional Court appointments.

The move comes as the country is still reeling from Yoon's

martial law, which he partly blamed on the opposition's

propensity to impeach government officials.

Han, 75, has served in leadership positions for more than

three decades under five different presidents, both conservative

and liberal.

His roles have included ambassador to the United States,

finance minister, trade minister, presidential secretary for

policy coordination, prime minister, ambassador to the OECD and

head of various think-tanks and organisations.

With a Harvard doctorate in economics, Han's expertise in

the economy, trade and diplomacy as well as a reputation for

rationality, a moderate demeanour and hard work had made him a

regular go-to man in South Korean politics.

Han has been prime minister since Yoon's term began in 2022,

his second time serving in the role after a stint as prime

minister under former president Roh Moo-hyun in 2007-2008.

"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 words

used to describe him when previous administrations tapped him

for key positions.

Han has experience working with South Korea's key ally the

United States, having been deeply involved in the process of

signing the U.S.-South Korea Free Trade Agreement.

Fluent in English, he was appointed South Korea's ambassador

to the United States in 2009, working in Washington at a time

when current U.S. President Joe Biden was vice president, and

contributed to Congress approving the Free Trade Agreement in

2011.

"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 who declined to

be identified.

Han's acting presidency was expected to last for months

until the Constitutional Court decides whether to remove Yoon or

restore his powers. If Yoon is removed, a presidential election

must be held in 60 days, until which Han will stay at the helm.

If parliament votes to impeach Han, the finance minister is

next in line among cabinet members to serve as acting president.

South Korea's Constitution does not specify how much the

acting president is empowered to do in carrying out the

leadership role.

Most scholars say the prime minister must exercise limited

authority to the extent of preventing paralysis of state affairs

and no more, although some say he can exercise all the powers of

the president, as the constitution imposes no restrictions.