Seoul, Jan 12 (IANS): South Korean President Yoon Suk Yeol will not attend the first formal hearing in his impeachment trial this week out of concerns for his safety, his lawyer said on Sunday.

Yun Gap-geun, Yoon's defence attorney, made the announcement as the Constitutional Court will hold the first oral arguments on Yoon's impeachment trial on Tuesday, while investigators are seeking to detain the impeached president for questioning in a separate case related to his short-lived martial law imposition, reports Yonhap news agency.

"As attempts to unlawfully execute an illegal and invalid arrest warrant are underway, there are concerns of personal safety and mishap," Yun said. "In order for the president to appear for the trial, the issue of personal safety and security must be resolved."

Yun said the impeached president will attend his trial if such issues are resolved.

The Constitutional Court earlier said it would start oral arguments for the trial on Tuesday, with a total of five hearing sessions scheduled until February 4.

Yoon's lawyers have previously said the president will attend his impeachment trial at an "appropriate" time to make his case.

Should Yoon fail to show up for the hearing on Tuesday, the court will be required to end the session and convene again on Thursday for a second session, which then can proceed even in Yoon's absence.

Investigators earlier sought to detain Yoon but failed after an hourslong standoff with the Presidential Security Service. They are widely expected to stage a second attempt to detain him after a Seoul court granted an extension of the warrant last week.

Separately, the president's lawyers visited the office of the state anti-corruption agency investigating Yoon on Sunday to deliver a notice of their appointment as Yoon's legal representatives.

During the visit, the lawyers reportedly stressed the need for talks to prevent a physical clash between the police and the presidential security service in their expected attempt to detain Yoon.