President Park Geun-hye has appointed a special prosecutor to independently investigate the political scandal plaguing her administration.

Opposition parties vowed on Wednesday to push ahead to try to impeach Park, rejecting her offer to resign if parliament demanded she do so. They also called on members of her own Saenuri Party to join forces with them. Thousands gathered in Seoul on the same day to demand Park resign as her approval rating plummeted to an all-time low of just 4 per cent.