South Korean prosecutors said on Monday they will seek an arrest warrant for ousted president Park Geun-hye, which would see her held in a cell for up to 20 days while being investigated on charges of taking bribes from big businesses.

Park, 65, became South Korea's first democratically elected president to be removed from office when a constitutional court upheld her parliamentary impeachment this month.

Park is accused of colluding with a friend, Choi Soon-sil, to pressure big businesses to donate to two foundations set up to back the former president’s policy initiatives.

She and Choi have denied wrongdoing.

In announcing the move to seek an arrest warrant, the prosecutors' office said there was reason to suspect that Park would try to destroy evidence.

"The case is very grave as the suspect has demonstrated acts of abuse of power by making companies give money and infringing on the freedom of corporate management by using powerful position and authority as president," the prosecutors' office said in a statement.

Park, who is currently free from detention, was questioned for 14 hours by prosecutors last week.

If the court grants the arrest warrant, Park will become the country's third former president to be detained in custody while being investigated.

Once Park is under arrest, the prosecutor will have up to 20 days to continue investigations, by which time they must file charges against her.

It was not clear when the court will hold a hearing on the arrest request.

Park could face more than 10 years in jail if convicted of receiving bribes from bosses of big conglomerates, including Samsung Group chief Jay Y. Lee, in return for favours.

Lee, who also denies charges that he provided bribes in return for favours for Samsung, and Choi are in detention and are separately on trial.