Rep. Lee Nak-yon, chief of the ruling Democratic Party (DP), stepped down from his post in the party Tuesday, in his bid to run for presidency next year.

The five-term lawmaker officially announced his resignation during a press conference in Seoul.

Lee's departure comes more than six months after he was elected as the DP chairman in late August and exactly one year before the next presidential election slated for March 9, 2022.

The resignation is in compliance with the DP's internal constitution that requires a party chief or a member of the top party council planning to run for presidency to give up their party positions at least one year before the presidential election.

The regulation is aimed at ensuring checks and balances between the presidency and the party leadership.

In the absence of a party leader, DP floor leader Rep. Kim Tae-nyeon will be doubling as acting party chairman until a new leader is elected in a party congress in May.

Even after his resignation as party chief, Lee will continue to serve as the co-chair of the DP's election strategy committee for the April 7 Seoul and Busan by-elections, as well as the chair of the special party committee in charge of a new airport construction project on Busan's Gadeok Island.

Lee is currently struggling to reclaim his previous lead in opinion polls of presidential hopefuls, which he has, since late last year, lost to DP-affiliated Gyeonggi Province Gov. Lee Jae-myung and Yoon Seok-youl, who resigned as prosecutor general last week. (Yonhap)