The hearing of Yoon's impeachment trial ended after four minutes in the president's absence, Seoul-based Yonhap News reported.
The next hearing of the trial has been set for Thursday and will proceed even if Yoon again decides to skip it.
Yoon, 63, was obliged to attend the first of five oral hearings by the top court over his martial law decree of Dec. 3.
He is facing trial after being impeached by parliament on Dec. 14 but is holed up in his official residence in the capital Seoul and has refused to entertain summons from investigators.
The top court has up to six months to decide whether to uphold or block the parliament impeachment of Yoon.
While Yoon remains suspended from his duties, an acting president from his Cabinet is running state affairs.
Separately, a joint team of anti-graft officials and police have asked presidential security and the Defense Ministry not to impede their second attempt to detain Yoon, who faces charges of insurrection and treason.
Some 200 security personnel from his security detail, as well as the Defense Ministry, had blocked the detention of Yoon on Jan. 3.
However, a court has extended the arrest warrant and the investigators have vowed to detain Yoon.
AzVision.az
More about: SouthKorea
