South Korea's Constitutional Court says it will hold the first oral arguments on January 14 in a trial to decide whether to uphold the National Assembly's impeachment of President Yoon Suk-yeol for his short-lived martial law declaration.

The court announced the plan on Friday at the second preparatory hearing, a procedure to sort out points of contention, evidence and other issues. It held the first such hearing on December 27.

Legal representatives for both the National Assembly and the president attended the hearing.

Yoon's legal team expressed staunch opposition to what it called a 'hasty' impeachment trial. A lawyer said much evidence must be presented, and testimonies must be extensively contested.

Yoon's lawyers also demanded the Constitutional Court act quickly on a call by Yoon's defense team for an injunction against a detention warrant for him.

Investigators entered the presidential residence early on Friday in an attempt to execute the warrant. Yoon's lawyer called the warrant illegal.

The National Assembly side demanded the oral argument sessions start without delay, saying such a situation that raises public concern should end as soon as possible.

The judge declared the court had wrapped up the preparatory proceedings, to move on to oral arguments.