The Australian government is making "urgent enquiries" with Russian authorities after a report Melbourne man Oscar Jenkins has been killed by Russian forces.
A spokesperson from the Department of Foreign Affairs and Trade (DFAT) said the report, on Seven News, had not been verified but the government had "grave concerns for Mr Jenkins's welfare".
Mr Jenkins, a 32-year-old teacher, was serving alongside Ukraine's armed forces when he was captured by Russian forces last year.
The spokesperson said the Russian ambassador to Australia was summoned to DFAT at the foreign minister's direction on Monday to seek information.
"The Russian Federation is obligated to treat all prisoners of war in accordance with international humanitarian law," the spokesperson said.
"DFAT is continuing to provide consular support to Mr Jenkins's family during this difficult time.
"His family has requested privacy and we ask that media respect their wishes."
Jenkins missing for months
At least seven Australians are believed to have died fighting in Ukraine since Russia's invasion began in 2022, but Mr Jenkins is believed to be the first to be captured and held as a prisoner of war.
A video surfaced in December showing Mr Jenkins being interrogated and hit by Russian forces.
that DFAT first learned of concerns for Mr Jenkins's welfare in November, and spoke to an American national who had fought alongside him, calling him "a damn good soldier" and adding he was "worried sick" about his welfare.
Mr Jenkins attended the Melbourne Grammar School and has been described as a "much loved" member of the Toorak Prahran Cricket Club. He has worked since 2017 as a lecturer in China.
Expel Russian ambassador if reports true, says Coalition
Coalition foreign affairs spokesperson Simon Birmingham said if reports of his "extrajudicial execution" were true, the government "should respond in the strongest possible terms" by expelling Russia's ambassador.
"Three years ago the then-Labor opposition urged Russian diplomatic expulsions, yet in government Labor have undertaken no such action," he said.
"If Russia has engaged in such an egregious and illegal action then it must now be a catalyst for action. Nothing less than the recalling of Australia's ambassador to Russia and expulsion of Russia's ambassador to Australia would be sufficient in such circumstances."
Russia is a party to the 1949 Geneva Convention which sets out rules for the treatment of prisoners of war, including that they are protected from violence.