Myanmar's Aung San Suu Kyi, 78, has spent her third birthday in a row under detention following the ouster of her democratically elected government in a military coup.

Suu Kyi, whose birthday fell on Monday, faces a total of 33 years in prison -- essentially a life sentence -- after being tried on 19 charges, including corruption and election fraud.

According to sources familiar with her situation, Suu Kyi is in a relatively healthy state. She has been held in a small building in the compound of a prison in the capital Naypyitaw since June last year, after being under house arrest.

Aung San Suu Kyi. (Getty/Kyodo)

Suu Kyi's younger son, Kim Aris, issued a video statement ahead of her birthday calling on the junta to release her and return power to a democratically elected government.

"This is an appeal firstly to the Burmese military to release my mother and all political prisoners and to commit to a ceasefire whilst opening negotiations to hand power back to the democratically elected government," Aris, who lives in Britain, said in the statement released Saturday.

Along with Suu Kyi, a Nobel Peace Prize laureate, other senior members of her government as well as other pro-democracy activists and politicians were arrested by the military after the coup, most of whom remain in detention.

Suu Kyi's now-dissolved political party, the National League for Democracy, on Monday urged the junta to hold dialogue with her to resolve political problems arising from the coup.

"We will work effectively in collaboration with allied countries and allied forces both inside and outside the country for the immediate release of all political prisoners without exemption, including Daw Aung San Suu Kyi," the party said in a statement, employing an honorific used for older women in Myanmar.

Activities to mark Suu Kyi's birthday have been held in areas controlled by the pro-democracy People's Defense Force, such as the Sagaing region of central Myanmar, as well as in other countries, local media reports said.

Many of her supporters in Myanmar posted photos of themselves with flowers in their hair -- similar to those often worn by Suu Kyi -- on social media Monday, in celebration of the democracy icon's birthday and as a peaceful protest to call for her release.

In the video statement, Aris also accused Japan and India of supporting the Myanmar military.

"It is disappointing, to say the least, that countries such as Japan and India which is supposed to be the largest democracy in the world will have anything to do with the junta," he said.

Aris said he is especially saddened as he has fond memories of having lived in both Japan and India as a child.

Activists and opposition groups have been criticizing India for reportedly selling arms to the military even after the coup.

The military is being accused of using excessive force against anti-junta resistance forces in the ongoing conflicts across the country.

The activists and groups have also condemned the Japanese government for not imposing sanctions on the junta, although many Japanese businesses have either left the country or gradually suspended their operations since the coup.

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