The National Assembly has approved the resignation of ruling Democratic Party(DP) lawmaker Lee Nak-yon.

The agenda item was referred to Wednesday's plenary session before the start of parliamentary inspections on government offices. In a vote attended by 209 lawmakers, 151 approved, 42 objected and 16 abstained. The DP now has 169 seats.

By-elections will take place in Seoul's Jongno district, which Lee represented, alongside the presidential election in March.

The former DP chairman announced he would step down as lawmaker last week so that he could focus on his bid to represent the party in next year’s presidential election. He is currently second in the party's primary behind Gyeonggi Province Gov. Lee Jae-myung.

Meanwhile, the main opposition People Power Party(PPP) also lost a seat this week as parliament approved the resignation of Yun Hee-suk. She offered to step down following the discovery of a possible speculation case involving her father.

The PPP now holds 104 seats. Her constituency, Seoul's Seocho district, will also hold by-elections in March.