New video shows captured Australian fighter Oscar Jenkins in Russian captivity

The federal government continues to hold "serious concerns" for Australian fighter Oscar Jenkins held by Russia after a video was posted online of him in captivity.

In the unverified footage, the 32-year-old former teacher from Melbourne is asked to give an update on his condition by a man filming.

"My name is Oscar Jenkins, I'm Australian," he says in the unverified video uploaded to YouTube about a week ago.

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He also says his arm remains broken, and his arm is "not good".

"I would like more freedom. No. My health. I feel a bit weak. I've lost a lot of weight."

The man filming, apparently one of his captors, says in English that Jenkins is a prisoner of war from the 66th Mechanised Brigade of the Ukraine armed forces.

The video was posted amid speculation about the wellbeing of Jenkins who was captured by Russian troops last December, the first known Australian to become a prisoner of war in the conflict.

"You are alive, so [the] information about your death is not right?" the man filming asks.

"Correct," the Australian responds.

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The video finishes with Jenkins being ordered to take off his beanie, which he does.

The man filming then says: "Everything is OK. He is alive and I think he will [be] better."

The Department of Foreign Affairs and Trade today renewed its demand for Russia to release Jenkins.

"We still hold serious concerns for Mr Jenkins' welfare," it said in a statement.

"Australia has made clear to Russia that Mr Jenkins is a prisoner of war and Russia is obligated to treat him in accordance with international humanitarian law.

"The government calls on Russia to release Mr Jenkins."

DFAT says officials continue to provide consular support to his family.

There were grave concerns for Jenkins last month after reports of his death.

But the Russian government quickly confirmed he was alive and in captivity.

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