Relatives of Myanmar's ousted leader Aung San Suu Kyi on Wednesday filed a complaint before a UN watchdog against her detention following a military coup last year, their lawyers said.

Since a coup ousted her government in February 2021, plunging Myanmar into upheaval, the 76-year-old Nobel peace prize laureate has been in military custody and faces a raft of charges that could jail her for more than 150 years.

Describing the situation as a "judicial kidnapping", human rights lawyers Francois Zimeray and Jessica Finelle said they had filed a complaint on behalf of her relatives with the UN Working Group on Arbitrary Detention.

"Her arrest was illegal, her detention is devoid of any legal basis, and her different trials violate the basic rules governing any legal procedure," reads the complaint, seen by AFP.

"This is a kidnapping disguised as a trial, she is held incommunicado in defiance of all justice and resists with strength an unacceptable psychological torture.

"This is a tragic regression for Myanmar. Through the figure of Aung Sang Suu Kyi, the entire Burmese people is silenced, and its democratic aspirations are crushed."

After facing a string of "farcical charges", Suu Kyi has so far been sentenced to a total of 11 years in prison, but faces the prospect of more than 100 more years on 17 different charges, the lawyers said.

Under a previous junta regime, Suu Kyi spent long spells under house arrest in her family's lakeside mansion in Yangon, Myanmar's largest city.

Today, she is confined to an undisclosed location in the capital, with her links to the outside world limited to brief pre-trial meetings with lawyers.

"Can anyone conceive what this detention entails for a (soon) 77-years-old woman, who has already spent 15 years of her life deprived of liberty?" Zimeray and Finelle asked.