"I will resign from my post if facts are clearly found that (I) received the money," Lee said before attending a session at the National Assembly.

Lee is one of eight heavyweight politicians listed on a "bribery list" left behind by Sung, who once served as a one-term lawmaker.

The memo showed won figures written next to the names of six out of eight politicians, indicating that they had received money.

No won figures were written next to Lee's name or that of President Park Geun-hye's current chief of staff, Lee Byung-kee.

Still, Sung claimed in a newspaper interview published Tuesday that he gave 30 million won ($27,000) in cash to Lee while Lee was running for a parliamentary seat in April 2013. Sung had the telephone interview with the newspaper just before his suicide.

"I have not even taken a penny from the former chairman Sung," Lee told reporters on his way to work.

The bribery allegation came a month after Lee declared an "all-out war" on corruption, saying the government will mobilize all its resources to root it out.

The presidential office said it is taking a wait-and-see attitude on Lee's alleged bribe-taking, citing a prosecution probe into the corruption scandal.

Lee said Monday that he will appear before prosecutors over their ongoing investigation into the scandal, if asked.

The prosecution has launched an investigation into the corruption scandal involving some of Park's close aides.

The eight politicians include Park's two former chiefs of staff -- Huh Tae-yeol and Kim Ki-choon -- as well as her current chief of staff, Lee Byung-kee. (Yonhap)