South Korea's National Assembly on Thursday passed three contentious bills pushed ahead by the main opposition Democratic Party of Korea, including one that mandates a special counsel probe into multiple allegations against first lady Kim Keon Hee.

The special counsel probe bill passed 167-0 by the opposition-led parliament during Thursday's plenary meeting is an updated version of the one vetoed by President Yoon Suk Yeol in January. The previous version focused on appointing a special counsel to investigate the first lady's alleged involvement in a stock manipulation scheme involving Deutsch Motors, a BMW car dealer in Korea, which goes back to 2009 and 2012, while the latest bill added several other allegations, including that Kim illegally interfered in the ruling party People Power Party's candidate nominations ahead of the April 10 general election.

It also calls for a more detailed probe into Kim's receipt of a luxury Christian Dior bag from a Korean American pastor, following the Seoul Central District Prosecutors Office's recent decision to drop graft, bribery and other charges against her following a four-month inquiry into the case.

The ruling People Power Party boycotted Thursday's plenary session, with its floor leader saying that all three bills would eventually be vetoed by Yoon yet again.

"Such bills passed by (the opposition-led Assembly) without the consent of both the ruling and the main opposition parties are bound to take the path of getting vetoed by the president," People Power Party Floor Leader Rep. Choo Kyung-ho said ahead of the meeting.

While the ruling party has staged multiple filibusters against the Assembly's moves to pass such bills pushed by the opposition since the 22nd Assembly session began in late May, Choo said they decided not to do so on Thursday.

"There was a decision (within the ruling party leadership) that it wouldn't be necessary to repeat (the filibuster) because we have already launched a filibuster on two different occasions (since late May) and have sufficiently explained the unjustness of the bills put forth this time," Choo explained.

The other two bills passed by the Assembly were: one that mandates a special counsel investigation into allegations that the presidential office and the Defense Ministry inappropriately interfered in the military’s probe into the death of Marine Cpl. Chae Su-geun, 20, and legislation requiring the government to fund a gift certificate program designed to support local small businesses as a form of local currency.

The previous two versions of the special counsel probe bill into the death of the young Marine conscript were also vetoed by Yoon in May and July this year, respectively. On the other hand, today's vote marks the first time the Assembly passed the bill to support the local gift certificate program.