An opposition-sponsored impeachment motion is almost certain to be adopted by the national assembly on Friday, with some 30 rebel MPs from Park's Saenuri party saying they will vote in favour.
The motion would then require the approval of the Constitutional Court, whose deliberations could take up to six months.
"Even if the impeachment bill is passed, I am resolved to continue calmly for the country and the people, while watching the Constitutional Court procedures," Park was quoted as saying by Saenuri parliamentary floor leader Chung Jin-Suk.
During an hour-long meeting with the president, Chung said he had told her that public sentiment had forced the Saenuri party to withdraw an earlier proposal for Park to step down voluntarily in April.
"She nodded and said she accepted my stance," Chung said.
Millions of South Koreans have taken to the streets of Seoul and other cities in a series of weekly mass protests demanding Park's ousting.
A protester wears a mask of South Korean President Park Geun-hye, during a rally on Nov. 30, 2016. (AAP) Source: AAP
During the latest rally on Saturday, there was particular anger directed against the Saenuri's resignation proposal, with protesters saying it was aimed at buying Park time and avoiding impeachment.
As a result the party withdrew its whip aimed at defeating Friday's motion and said its MPs would be allowed to vote freely according to their conscience.
Hwang Young-Cheul, one member of an anti-Park faction within the party, said the idea that the president could step down in April had "already been rejected by the people".
"All preparations have been made that are necessary to ensure the impeachment motion be passed," Hwang said.
The scandal that has engulfed Park and paralysed her administration has focused on her friendship with long-time confidante Choi Soon-Sil.
Choi has been charged with meddling in state affairs and using her Blue House connections to force dozens of conglomerates to donate around $70 million to two foundations she controlled.
In a first for a sitting South Korean president, Park has been named a "suspect" by prosecutors investigating Choi.
While she retains the presidency, Park cannot be charged with a criminal offence except insurrection or treason, but she would lose that immunity once she leaves office.
