The largest opposition party in South Korea has declared that it will introduce legislation to remove acting President Han Duck-soo from office.

Han had been threatened with impeachment by the opposition Democratic Party if he did not name three justices to the Constitutional Court right away.

Three nominees were approved by Parliament on Thursday, but Han has not yet formally appointed them.

President Yoon Suk Yeol is being impeached by the judiciary for declaring martial law on December 3.

Prime Minister and interim President Han Duck-soo lacks the qualifications and the will to protect the Constitution, according to a statement made by Park Chan-dae, the floor leader of the Democratic Party.

The finance minister will take over as acting president in the event that Han is impeached.

The Democratic Party has majority control of parliament, but there is disagreement between the parties and some constitutional scholars over whether a simple majority or a two-thirds vote is needed to impeach the acting president.

Han said earlier on Thursday that he will not appoint the justices until political parties reach agreement on the appointments, adding that doing do so without political consensus would harm constitutional order.

Han has been under pressure to make the appointments, but political parties have disagreed on whether he has the authority to do so as acting president.

The court is set to hold its first hearing on Friday in the trial to decide whether to remove Yoon or reinstate him.

Under the constitution, six justices must agree to remove an impeached president, meaning the current justices must vote unanimously to remove Yoon.

Court Spokesperson, Lee Jean, in a media briefing, said Yoon, who was impeached by parliament on December 14 in a vote joined by some members of his centre-right party, has not submitted legal papers as requested by the court as of Thursday.

Yoon’s repeated defiance has sparked criticism and calls from the opposition for his arrest.