Australia has vowed it will take the “strongest action possible” if Russia has harmed one of its nationals captured fighting for Ukraine, after reports emerged the prisoner of war may have been killed.

Australia's Prime Minister Anthony Albanese has vowed to take decisive measures if harm has been inflicted on Oscar Jenkins, a Melbourne school teacher captured while fighting for Ukraine. Disturbing video footage from December shows Jenkins being interrogated by Russian forces.

There are fears an Australian man captured by Russian forces while fighting for Ukraine has been executed. Oscar Jenkins, a 32-year-old teacher from Melbourne, was reportedly captured in the Donbas region.