This photo shows President Yoon Suk Yeol (right) and Democratic Party of Korea Chair Rep. Lee Jae-myung during their formal talks at the presidential office in Seoul on Apr. 29. (Yonhap)

President Yoon Suk Yeol's office rejected Democratic Party of Korea Chair Rep. Lee Jae-myung's proposal to hold formal talks with Yoon to narrow differences on a pension reform bill that would require people to contribute more while employed and benefit them more after retirement, Lee's aide told reporters Friday.

Yoon's aide on political affairs Hong Chul-ho turned down Lee's proposal for either two-way talks between Yoon and Lee, or three-way talks between Yoon, Lee and the ruling party interim leader Hwang Woo-yea, according to Rep. Cheon Jun-ho, the opposition party leader Lee's chief secretary. The two held their first ever meeting in late April.

"Hong told us that it is inappropriate for the President to hold talks with political party leaders at a moment when bipartisan talks (over the pension reform) did not bear any fruit," Cheon said. "We take (Hong's) comment as a disapproval of not only the two-way talks but also the three-way talks."

Yoon's office was not immediately available for comment on the matter.

Earlier Friday, Lee said the parliament's efforts to achieve pension reform "cannot go back to square one" as the 21st National Assembly is to terminate next week with its final plenary session scheduled for Tuesday. All ongoing legislative discussions will start from scratch as the new National Assembly begins on May 30.

Instead, Lee asked the National Assembly to find common ground over the matter, and urged Yoon to come to the negotiating table over the parliament's pension reform, in the country where demographic shifts are raising doubts about the national pension fund's sustainability.

"An agreement must be reached at any rate, through President Yoon Suk Yeol's meeting with the Democratic Party chief, or Yoon's meeting with leaders of the ruling and opposition parties," Lee said at a party meeting at the National Assembly Friday.

Also on Thursday, Lee said on his social media post he was "willing to hold talks with the President" over pension reform.

Currently, South Korea's public pension requires an employee and the employer to pay a matching contribution equal to 9 percent of the employee's monthly earnings, and as of 2024, employees will receive 42 percent of wages in pension benefits each month starting at the age of 65.

This is a result of the latest 2007 reform meant to gradually decrease the benefit level from 50 percent to 40 percent by 2028, while maintaining the contribution level at 9 percent.

Lee's main opposition has pushed ahead with the plan to increase the contribution level to 13 percent of employees' wage, and benefit level to 45 percent.

The ruling party, on the other hand, also proposed to increase the pension contribution level to 13 percent, but increase the benefit slightly less, to 43 percent.

They have been unable to narrow their differences over the 2 percentage point difference, despite the efforts of a special National Assembly committee.

Lee reiterated the party's proposal Friday, saying now is the time for the government to "make a bold decision."

Lee said Friday the government had "unofficially proposed to raise the pension benefit level to 45 percent." On Thursday, Lee said the party complied with the government's proposal to speed up the reform.

The ruling party denied Lee's argument, labeling Lee's remarks as "a lie."

Yoon and Lee first met on Apr. 29, for the first time since Yoon took the oath of office in May 2022. Lee, formerly a presidential election contender who lost to Yoon, discussed current affairs and ways for bipartisanship in their April meeting.

The Itaewon special probe bill passed the parliament following the talks. But the two parties' relations immediately turned sour after the opposition party passed another bill to probe an investigation into a Marine soldier's death, without debating on this matter with the ruling party.

The main opposition party holds a majority of seats at the 21st National Assembly. It will do so too in the 22nd National Assembly.