Korea's left-wing party said Monday it will this week expel two of its lawmakers suspected to have been involved in a rigged primary, after initially failing to do so because of strong opposition from the party's main faction.

The embattled Unified Progressive Party (UPP) was engulfed in turmoil over allegations that its primary vote, conducted in March to name proportional representation candidates to run in the April 11 parliamentary elections, was rigged.

Last week, the party elected Kang Ki-kab, a reformist as its new chairman.

That appointment has been seen as crucial in determining the fate of two UPP lawmakers -- Lee Seok-ki and Kim Jae-yeon -- who have been under pressure to leave the party due to their suspected involvement in the rigged primary. Kang has demanded that Lee and Kim be expelled from the party.

The two lawmakers, who have separately come under fire for allegedly espousing the North's "juche," or self-reliance, philosophy, would become independent lawmakers if ousted from their party. (Yonhap News)