Conservative People Power Party(PPP) presidential candidate Kim Moon-soo has announced plans to take immediate legal and political action against the party leadership's push to replace him, calling the move "illegal and unjust."

At a press conference on Saturday, Kim said the PPP's interim leadership "illegally stripped" him of the candidacy overnight, after he was fairly elected by the public and party members.

Kim said the "political coup d’état" in the middle of the night is an "anti-democratic incident" unprecedented not only in South Korea's constitutional history, but also around the world.

Kim vowed to hold those responsible legally and politically accountable.

After launching a process overnight to replace Kim with former Prime Minister Han Duck-soo, the PPP plans to conduct a vote among its party members until 9 p.m. Saturday, before approving it through the national committee on Sunday.