South Korea's first trans soldier, Byun Hui-su, has said she will battle a ruling that she can no longer serve in the military. (Screen capture via YouTube)

The fate of a trans soldier who underwent gender confirmation surgery has been sealed after the South Korea military decided to discharge her.

In what proved to be a test case for the country’s handling of LGBT+ rights, the staff sergeant in her 20s wished to continue serving in the army as female.

However, a military panel voted to throw her out, a ruling that Byun Hui-su has vowed to “fight”, Reuters reported.

‘I will continue to fight until the day I can remain to serve in the army.’

Stationed in the Gyeonggi Province, north of Seoul, Hui-su’s hope of serving in the female corps caused tremors in the country.

Trans folk are barred from joining the military, but no specific legislation is in place on those active-duty members who transition during their time in service.

The military said in a statement that Hui-su’s surgery is grounds for discharge, bringing an end to her service.

But even before the ruling was finalised today, she had already planned to file a lawsuit against the army, whatever means necessary.

“I will continue to fight until the day I can remain to serve in the army,” she said in a press conference.

“I’ll challenge the decision until the end, to the Supreme Court.”

Hui-su’s broke down in tears in front of reporters as she described her decision to transition – to live her truth – after years of distress and bouts of depression.

“It was an extremely difficult decision to let my base know of my identity, but once I did, I felt much better,” she told reporters at a news conference in Seoul after the military announced its decision.

“I thought I would finish serving in the army and then go through the transition surgery and then reenter the army as a female soldier.

“But my depression got too severe.”

LGBT+ soldiers ‘treated like criminals’ in South Korea.

Hui-su’s decision to battle the trans troops ban is one that has sparked a national debate over LGBT+ rights in South Korea, where laws often clash with queer people’s rights.

Military service is mandatory for men, but under the Military Penal Code, gay men are considered to have a “personality disorder”, and being identified as such can lead to institutionalisation or discharge.

Activists have long argued that such laws are discriminatory and unconstitutional, with many packing courtrooms in attempts to strip the anti-LGBT+ articles from law.

However, their attempts so far have proved hollow, with today’s ruling being yet another setback for LGBT+ rights in South Korea.

The Seoul-based Military Human Rights Centre accused the military of treating LGBT+ troops “as if they are criminals”.