The control of South Korea's military forces currently lies with President Yoon Suk Yeol as the commander in chief, the defense ministry said Monday, as he faces investigation as a suspect on treason charges over last week's martial law declaration.

On Sunday, prosecutors said they booked Yoon as a suspect on insurrection charges after his surprise declaration of martial law Tuesday night that was unanimously rejected by the National Assembly hours later.

"Legally, (the control of military forces) currently lies with the commander in chief," the defense ministry's spokesperson Jeon Ha-kyou said in a regular briefing when asked whether a suspect in an insurrection case can hold such powers.

Han Dong-hoon, leader of the ruling People Power Party, said Sunday Yoon would step away from state affairs, such as diplomacy, until he leaves office.

When asked by reporters if that also would include Yoon's control over the military, Han said, "I think that would be the same. It would cover diplomatic affairs." (Yonhap)