First Lady Kim Keon-hee attends a ceremony marking the 77th anniversary of Liberation Day held at the presidential office in Seoul, Aug. 15. Newsis

The main opposition Democratic Party of Korea (DPK) decided Wednesday to introduce a bill later in the day mandating an independent counsel probe of first lady Kim Keon-hee over allegations of stock manipulation and other irregularities, the party's floor leader said.

The move is seen as a counterattack against the administration of President Yoon Suk-yeol conducting a prosecution investigation of DPK leader Lee Jae-myung, which the party has denounced as "political revenge" against the former presidential candidate.

DPK floor leader Rep. Park Hong-keun said during a Supreme Council meeting that the special investigation proposal is aimed at uncovering the truth behind allegations of stock manipulation and academic credential falsification involving the first lady.

Rep. Park Hong-keun, center, floor leader of the Democratic Party of Korea, speaks during a party meeting at the National Assembly, Sept. 6. Yonhap

Claiming the public's fury is "spreading like wildfire," Park urged Kim to issue a formal apology and warned the ruling party People Power Party against defending her unconditionally.

Prosecutors have been investigating the chairperson of Deutsch Motors Inc., a BMW car dealer in South Korea, over allegations of mobilizing influential market players, including the first lady, in order to boost Deutsch Motors' stock prices starting in December 2009 for about three years.

The first lady has also faced suspicions that she submitted false records of her academic and career background on multiple resumes, including one for a teaching job at Kookmin University, which she ultimately secured in 2014. (Yonhap)