A lawmaker of the ruling Democratic Party tendered his resignation on Monday over sexual harassment allegations, despite his party's call for him to stay on until the accusations are verified.

Min Myung-doo, a three-term lawmaker, offered to step down Saturday shortly after the alleged victim claimed in a media interview that he had sexually harassed her at a karaoke bar about a decade ago.

Min, who has been preparing to run in the Seoul mayoral election in June, has denied any "problematic" behavior. But he said he would leave the parliament anyway even for the "slightest mistake" that he was unaware of.

"As I have already said, I am going to resign as lawmaker ... This is the decision that I have made, and I am thankful to those who have paid attention to my words," Min said in a text message sent to reporters.

"Wherever I am, I will contribute to promoting the public good," he added.

A lawmaker's resignation can be finalized with parliamentary approval or the National Assembly speaker's permission when the legislature is in recess. Observers said his resignation is expected to be confirmed sometime next month.

Earlier in the day, the ruling party decided to wait until the "facts" are verified rather than immediately accepting his resignation -- in contrast to its quick decision last week to expel a former provincial governor accused of sexually assaulting his former secretary.

Observers said that the party's reservations appear to reflect its concerns that a loss of even a single lawmaker could make it lose its status as the largest group in the National Assembly.

The ruling party has 121 lawmakers, including Min, just five more than the main opposition Liberty Korea Party. The LKP could become the largest party should it win in the June by-elections where at least eight parliamentary seats are up for grabs.

According to the legislature's custom, the largest party is entitled to recommend a parliamentary speaker who wields broad authority in legislative affairs, such as tabling disputed bills for a floor vote. The two-year term for current parliamentary chief Chung Sye-kyun is set to expire in May. (Yonhap)