Earlier in the day Park Geun-hye said in a speech that she was ready to resign if the parliament worked out a safe power transition procedure.
"The speech lacked self-reflection and repentance. What people want is her immediate resignation, not dragging it out and passing the responsibility to the parliament," Youn Kwan-suk, the spokesman of the main opposition Democratic Party, was quoted as saying by South Korean Yonhap News Agency.
Political scandal around the president broke out when media reported that Park allowed Choi, who held no official post, to edit her speeches thus letting her influence the country's policy. Moreover, Choi was suspected of pressuring South Korean big corporations and extorting money from them for her noncommercial funds. A total of $70 million was transferred to the bank accounts of these funds.
Choi was officially charged on November 20 and the prosecution said that the president was also involved in the scandal. As a result, thousands of people took to the streets demanding the president's resignation.