Watch| Ukraine releases startling 'before' and 'after' images of former PoW

The Ukraine defence ministry published images of soldier Mykhailo Dianov who was recently released from captivity showing stark contrasts between his time as a trooper and his time in captivity.

Along with the images, Ukraine also accused Russia of not adhering to the Geneva Conventions. The ministry went on to add that Russia's treatment of Prisoners of War is how it continues the legacy of nazism.

Dianov, according to Ukraine, is one of the 'fortunate ones' to have survived Russian captivity, 'in contrast with some of his fellow POWs'.

In the released images, Dianov appears frail with bruises on his arms and a hollow face.

While in the image captured in May, the soldier is seen smiling as he dons the military uniform.

Advisor to the Ukrainian foreign ministry, Anton Gerashchenko, said that he was missing four centimetres of bone in one arm.

Also Watch| Ukraine says it has reclaimed more territory, captured Russian soldiers

"Treatment and rehabilitation will take a long time now (and more pain)," he added. "That's all we need to know about captivity."

Mykhailo's sister Alona Lavrushko reportedly told the media that her brother is currently admitted to the Kyiv Military Hospital where he remains in a serious condition and will require long-term treatment.

"The doctor in the military hospital has taken a look at him. They're not going to operate on him just yet; he needs to gain some weight first. That's the main thing because he can't be operated on in his condition. It could be dangerous for his health. So he has to recover now and gain strength. His physical condition is serious, of course," she added.

Dianov, reports Telegraph, was detained earlier this year while fighting to defend the Azovstal steel plant in Mariupol. He was one of over 200 soldiers released from captivity last week.