The main opposition Democratic Party (DP) plans to file a resolution next week calling for the resignation of National Assembly speaker Kang Chang-hee over his alleged violation of parliamentary laws in support of the ruling party, a DP spokesman said Friday.

The move comes a day after Kang put to a vote the motion for the confirmation of Hwang Chan-hyon -- President Park Geun-hye's nominee for the head of the Board of Audit and Inspection -- amid objections from the opposition party.

A plenary session of the National Assembly approved the motion 154-3 while the DP boycotted the vote in protest of Kang's denial of its request for a filibuster.

"The confirmation motion's passage is invalid, and we will take corresponding measures," DP floor spokesman Park Soo-hyun said in a press briefing. "We plan to file a resolution for Speaker Kang's resignation next Monday."

If filed, the resolution is unlikely to pass through the National Assembly as the ruling Saenuri Party currently holds the majority in the 300-seat parliament with 155 seats. The DP holds 127 seats, with the rest claimed by minor parties and independents.

(Yonhap News)