The Constitutional Court in South Korea has five trial dates scheduled between January 14 and February 4. The impeachment process will be held without Yoon if he does not appear.
"There has been concern about security and potential incidents. Therefore, the President will not be able to attend the trial on January 14," says his lawyer in a statement.
"The President is willing to appear at any time when the security issues are resolved."
Since Yoon was removed from his post in December, after being impeached, he has refused to meet prosecutors and investigators. Instead, he has locked himself in his residence, protected by guards.
The police have made several attempts to arrest him – but without result. In Seoul, the capital of South Korea, where Yoon has his residence, both opponents and supporters of his have gathered almost daily for protests.