Ukraine is "taking all the necessary measures" to save the three foreign nationals who were sentenced to death by authorities in the Donbas, a lawmaker in Ukraine’s parliamentary security and defence committee has said.
Britons Aiden Aslin, 28, and Shaun Pinner, 48, were captured in Mariupol in April during the intense fight for control of the port city.
Both were found guilty of "mercenary activities and committing actions aimed at seizing power and overthrowing the constitutional order of the Donetsk People’s Republic" and sentenced to death this week.
A Moroccan national called Saaudun Brahim was also convicted alongside Mr Aslin and Mr Pinner.
Ukrainian lawmaker Fedir Venislavskyi said on national television: "Both the defence ministry and the main directorate of intelligence, which deals with the exchange of prisoners, are taking all necessary measures to ensure these citizens of foreign states are saved."
He did not give further details.
Foreign Secretary Liz Truss discussed efforts to secure the release of Aiden Aslin and Shaun Pinner with her Ukrainian counterpart on Friday, after the judgment by a Russian proxy court.
Ms Truss said she discussed “efforts to secure the release of prisoners of war held by Russian proxies” during her call with Dmytro Kuleba, Ukraine’s minister of foreign affairs.
“The judgment against them is an egregious breach of the Geneva Convention,” she added.
Meanwhile, Ukraine’s deputy prime minister Iryna Vereshchuk said she believed the separatist authorities would ultimately act rationally, "for they are well aware of the irreparable implications for them and for the Russians if they take any wrong steps against these three of our soldiers."
"Something tells me that, eventually, one way or another, sooner or later, these three servicemen will be exchanged (or otherwise get home)," she said in an online post.
In a statement, they said: “As a Ukrainian resident for over four years and contracted serving marine in the 36th Brigade, of which he is very proud, Shaun should be accorded all the rights of a prisoner of war according to the Geneva Convention and including full independent legal representation.
“We sincerely hope that all parties will co-operate urgently to ensure the safe release or exchange of Shaun. Our family, including his son and Ukrainian wife, love and miss him so much and our hearts go out to all the families involved in this awful situation.
“We respectfully ask for privacy from the media at this difficult time.”
The rallying call from the prime minister came as Diana Okovyta, Mr Aslin’s fiancee, travelled to London to try to campaign for his release.
And in an emotional social media post, she assured her partner that he was not "abandoned".
She said: "How I wish you knew you aren’t forgotten, you’re not alone, you are not abandoned and will not be forsaken.
"I hope that anyway deep down in your soul you know and feel it. I believe that soon in newspapers we will see pictures of you smiling."
