During Wednesday's session, Park's former key aides, including an ex-chief of staff, testified about suspicions that Choi and her associates meddled in government affairs.

Choi was arrested last month on charges of abuse of power, coercion and fraud. Prosecutors said Park was also an accomplice.

The focus of Wednesday's hearing is expected to be on Kim Ki-choon, former presidential chief of staff, who exerted immense influence in the Park administration.

Kim Ki-choon said he wishes to express an apology for the scandal, adding he failed to properly assist the president.

Cha Eun-taek, a former commercial director who is alleged to have used his connections with Park's confidante to pocket profits, denied suspicions that he entered the presidential office at late hours for secret communication with Park.

Cha did admit to meeting Kim Ki-Choon and former Vice Culture Minister Kim Chong. Cha said the meeting took place at Choi's request and was only intended to exchange greetings. Cha, however, said he "partially" admits to the allegations that he exerted influence on personnel issues and advertisement projects for KT Corp., a local mobile carrier.

Former Vice Culture Minister Kim denied allegations that Kim Ki-choon requested he provide favors to Choi's daughter. The vice minister said he only knew about Choi through an acquaintance after he became the vice culture minister. He also denied the allegation that he sought to pressure swimming champion Park Tae-hwan to give up running for the Rio de Janeiro Summer Olympics, adding the suspicion is attributable to a misunderstanding.

The vice culture minister, however, admitted expressing discontent with figure skating star Kim Yu-na, but declined to comment on the reasons.

On Tuesday, the parliamentary committee grilled the heads of eight conglomerates on their alleged connections to Choi. They were found to have donated to two nonprofit foundations controlled by Choi. She is suspected of embezzling money from them. (Yonhap)