South Korean President Roh Moo-hyun has reshuffled his cabinet, appointing new commerce and unification ministers.
Lee Jong-seok, an expert on North Korean affairs, is to replace Chung Dong-young as unification minister, according to the Blue House.
The head of the ruling Uri Party, Chung Sye-kyun, is the new minister for commerce, industry and energy.
Analysts say the changes are aimed at boosting the image of the Uri Party ahead of local elections in May.
The reshuffle is the first of a planned two-part shake-up.
Lee Jong-seok, who is taking on the high-profile unification portfolio overseeing relations with North Korea, is known as a supporter of continued engagement with Pyongyang.
Mr Lee "has played an important role in building the government's diplomatic and security philosophy and establishing a security strategy," the Blue House said in a statement.
Former Unification Minister Chung Dong-young stepped down last week, in order to concentrate on campaigning for the Uri Party ahead of the elections.
Mr Chung is considered one of the most likely candidates to take over from Mr Roh as president in the 2007 elections.
Former Health Minister Kim Keun-tae also resigned last week, to campaign for the party.