Russian prosecutors said today that Jenkins, 33, was paid around $15,000 a month to fight in Ukraine after he travelled from Melbourne to fight in the war against Russia.

He was filmed in the courtroom today as guards released him from his handcuffs and put him behind a glass wall for court proceedings.

He briefly glanced at the camera before he heard his sentence of 13 years behind bars in a Russian prison.

Jenkins was taken into Russian custody in December last year.

He was captured in occupied eastern Ukraine and the Australian government has been calling for his release since.

One significant issue Jenkins is facing is that he is not being treated as a prisoner of war.

Instead, Russian authorities have called him a mercenary because he travelled from overseas to work alongside Ukrainian forces.

In the months since he was captured, there have been increasing concerns about his welfare. 

At one point, there were false reports that he had been killed, until video surfaced of Jenkins looking frail and being taken into Russian captivity.