Yoon Suk Yeol remains under a travel ban as authorities continue a separate probe into his Dec 3 martial law declaration.
South Korea's constitutional court kicked off proceedings on Monday over the impeachment of President Yoon Suk Yeol, who has been suspended from office over his failed bid to impose martial law.
Prosecutors issued Yoon with a second summons on Monday for questioning over insurrection and abuse of power allegations after he "refused to comply" with a similar request a day earlier.
Members of parliament in Seoul voted to impeach the president on Saturday after he imposed a short-live martial law order that thrust the country into political chaos.