The 76-year-old's civilian government was ousted in a coup last year that triggered mass protests, and she faces a raft of charges that could see her jailed for more than 150 years.

Currently on trial for alleged corruption, breaching Myanmar's official secrets act and pressuring the election commission, Suu Kyi has not appeared in court since last Thursday, the legal source told AFP.

"Some people in her company have been infected by Covid-19... and so she's kept in quarantine, although she's not infected," the source said.

"We are worried because we haven't been able to see her."

Former president Win Myint -- charged alongside Suu Kyi -- appeared at the court on Monday via video conferencing, the source added.

Suu Kyi and her personal staff have been fully vaccinated against Covid-19 since being taken into military custody, her lawyer told AFP last July.

She missed a hearing in September due to illness, and in October, her lawyer said her health had suffered from her frequent appearances before the junta-run court.

Journalists are barred from the proceedings in the military-built capital Naypyidaw, and her lawyers have been banned from speaking to the press.

Suu Kyi was previously sentenced to a total six years in jail for incitement against the military, breaching Covid-19 rules and breaking a telecommunications law -- although she remains under house arrest while she fights other charges.