The son of Myanmar democracy leader Aung San Suu Kyi is "concerned" about her health, he said on Wednesday, as the Nobel laureate turned 79, passing another birthday in military detention.

Suu Kyi has been detained by the military since it toppled her government and seized power in 2021, plunging the Southeast Asian nation into turmoil.

The Nobel laureate is serving a 27-year sentence imposed by a junta court after a trial condemned by rights groups as a sham to shut her out of politics.