The lawyers for a former South Korean defence minister under investigation on insurrection charges said on Thursday a short-lived martial law decree imposed earlier this month was to raise alarm on opposition parties' abuse of the democratic process.

South Korea’s President Yoon Suk Yeol again declined to appear for questioning by investigators over his martial law declaration as the embattled leader seeks to first defend himself at an impeachment trial.

South Korea's suspended President Yoon Suk Yeol did not respond on Wednesday to a second summons by anti-corruption authorities who, along with prosecutors, are investigating his short-lived martial law decree issued early this month.

South Korean President Yoon Suk Yeol failed to appear before law enforcement authorities for questioning on Wednesday - the second time he has ignored a summons over his attempt to impose martial law.