*

Han Duck-soo becomes interim leader after Yoon's

impeachment

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Han's leadership may last months

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Han to manage government during gravest political crisis

in 4

decades

By Joyce Lee

SEOUL, Dec 14 (Reuters) - Prime Minister Han Duck-soo,

who became South Korea's acting president after Saturday's

impeachment of Yoon Suk Yeol, is a career technocrat whose

wide-ranging experience and reputation for rationality could

serve him well in his latest role.

With parliament's impeachment vote against Yoon passed after

his short-lived attempt to impose martial law, Yoon is suspended

from exercising presidential powers, and the constitution

requires the prime minister to take 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 faces a 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.

His tenure as acting president could also be threatened by

criminal investigations into his role in the martial law

decision.

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, moderate demeanour and hard work has 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.

"I think Han is the right candidate to carry out national

affairs while overseeing and coordinating the Cabinet, with a

wealth of experience that encompasses public and private

sectors."

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.

Han has also served as board member of S-Oil, a

South Korean refining unit of Saudi Aramco.

"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 role in leadership is 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.

The main opposition Democratic Party has filed a complaint

against Han to be included in the investigations for failing to

block Yoon's attempt at martial law.

If parliament decides 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

prime minister 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 put no restrictions.