South Korea's parliament is set to hold separate hearings with key figures in the corruption scandal surrounding Choi Soon-sil in prison, the investigation committee said Friday.

The key witnesses, including President Park Geun-hye's confidante Choi, have repeatedly rejected parliament's request to appear at the National Assembly to answer questions about their roles in the scandal that has led to the impeachment of the chief executive. The 60-year-old has been in custody since late October on charges of conspiring with the president for personal gain. Choi is also under suspicion of influencing state affairs by abusing her decades-long friendship with the president.

The committee will hold a hearing for Choi at 10:00 a.m. on Monday at her detention center located in Seoul.

Later in the day, it will also grill Ahn Jong-beom, former senior presidential secretary for policy coordination, and Jeong Ho-seong, former secretary for private presidential affairs, at a separate detention center.

The committee said it has no choice but to carry out on-site hearings as the key figures refused to cooperate, citing the ongoing criminal investigation and health issues.

Political observers, however, said the three are unlikely to respond to questions, even if lawmakers visit their cells. (Yonhap)