SEOUL, Sept. 2 (Yonhap) -- Sohn Hak-kyu, a veteran politician and former provincial governor, was elected the new chief of the minor opposition Bareunmirae Party (BP) on Sunday, vowing efforts to achieve political reform and intraparty unity.

The 71-year-old politician was picked to lead the third-largest party at a national convention, beating five rival candidates.

When announcing his bid last month, Sohn said if elected, he would devote himself to making the BP play a central role in driving reform in Korean politics.

Sohn, a former four-term lawmaker, served as the chairman of the now-ruling Democratic Party (DP) in 2010-2011 when it was the main opposition party. He was Gyeonggi Province governor from 2002 to 2006, when he was affiliated with the conservative Grand National Party, the predecessor of the now-main opposition Liberty Korea Party (LKP).

In his acceptance speech, Sohn lashed out at both the ruling DP and the leading opposition LKP for their increasing self-righteousness and division stemming from apparently unchecked power.

"We have to muster all our power to fight the two parties that are messing up Korean politics," Sohn said.

He also vowed to devote himself to tearing down what he called an imperialistic presidency of incompetence and self-righteousness and the current unbridled and unchecked two-party system.

The LKP, meanwhile, congratulated him on his election and stressed the need for cooperation and coexistence between the two opposition parties.

"We sincerely hope that the new BP leadership will cooperate as a proper opposition party in preventing and keeping in check the ruling party forging ahead by itself," an LKP spokesman said.

Sunday's election came as former co-leaders resigned following the party's crushing defeat in the June 13 local elections.

The BP is facing its biggest crisis following its election defeat. It won none of the 17 big-city mayoral and gubernatorial posts and 12 parliamentary seats in the first nationwide polls for the party.

Currently, the party holds 30 seats in the 299-member National Assembly.

Ahn Cheol-soo, one of the party's founders, has decided to stay away from politics for a while after he finished in third place in the Seoul mayoral race in June.

The BP came into being in February through a merger of two center-right and center-left parties, in what is seen as a bold experiment in South Korea's politics long dominated by regional and ideological divisions.

But voters' support for Ahn and his party has been on the wane, apparently because he failed to deliver his promise to practice new politics.

Sohn's election added to the return of political bigwigs to the political main stage, which some critics derisively call the comeback of "old boys."

In August, Lee Hae-chan, a 66-year-old, seven-term lawmaker, was elected the new chief of the ruling DP.

Four-term lawmaker Chung Dong-young, 65, was picked last month to lead the minor opposition Party for Democracy and Peace.

Source: Yonhap News Agency