The outgoing chief judge of South Korea's Constitutional Court urged the court on Wednesday to conclude the impeachment trial of President Park Geun-hye by March 13, when the retirement of another judge will reduce the nine-judge bench to seven.

Park was impeached amid a corruption scandal that has engulfed her administration over recent months. If the impeachment is upheld, she will become the first democratically elected leader to be removed from office.

Chief Judge Park Han-chul, who retires on Jan. 31, said on the ninth day of the impeachment hearing that the retirement of two judges may distort the court's impartiality.