Patron of the National League for Democracy (NLD) Tin Oo, 90, had reportedly regained consciousness following a serious case of concussion after a fall at his home.
He was initially sent to Shwegonedine Hospital on May 17, moved to Yangon General Hospital’s neurology department and then to the intensive care unit when his condition worsened.
The hospital's superintendent Dr Aye Ko Ko said a special committee had been formed for Tin Oo as his condition was unstable due to his old age and ongoing chronic diseases.
NLD members waiting at the hospital said he fell in the shower.
He was commander-in-chief from 1974 to 1976.
Tun Kyi from the Former Political Prisoners Society said: ”I encourage everyone to send well wishes and prayers his way."