Seoul, April 16 (IANS): South Korean Prime Minister Lee Wan-koo on Thursday rejected rumours of his resignation over his alleged involvement in a bribery scandal.

"I will perform my official duty without any agitation," Lee said, attending a National Assembly session.

The move came soon after Moon Jae-in, the leader of the main opposition New Politics Alliance for Democracy, threatened to impeach the premier unless he steps down over the bribery scandal, Yonhap News Agency reported.

Lee is accused of accepting 30 million won ($27,000) in cash from a late businessman in 2013, when Lee was running for a parliamentary seat. He has repeatedly denied the accusation.

Before his suicide last week, Sung Wan-jong, a former head of a mid-size construction firm, claimed he gave up to several millions of dollars to the prime minister and seven other former and current high-profile politicians.

"If he continues to hold onto his seat, our party will consider presenting a dismissal proposal," Moon said.

According to South Korean law, parliament can initiate an impeachment motion against a prime minister if a third of the lawmakers endorse it.

So far, no South Korean prime minister has been impeached.