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 earlier this month.

Yoon had not appeared for questioning as of 10 a.m. on Christmas Day as requested by the Corruption Investigation Office for High-ranking Officials (CIO), after ignoring its first summons last week.

An agency official said it would continue waiting for Yoon on Wednesday, adding it would need to review the case further before seeking an arrest warrant, Yonhap news agency reported.