The Russian Embassy in the UK has caused outrage after it tweeted a call for Ukrainian fighters to be executed in a "humiliating death".
A video posted on the embassy’s official account showed a man said to be from Mariupol suggesting fighters from the Azov battalion should be hanged.
The clip claimed the man and his wife had been shelled by Azov fighters following Russia's invasion of Ukraine.
The Russian Embassy quoted the man in a tweet, writing: “#Azov militants deserve execution, but death not by firing squad but by hanging, because they’re not real soldiers. They deserve a humiliating death.”
It comes after Russia and Ukraine blamed each other for an attack which killed 40 Ukrainian prisoners of war, including some from the Azov battalion.
Watch: Dozens of Ukrainian POWs killed in missile strike
UK and Ukrainian officials criticised the post and called for the Russian Embassy to banned from Twitter.
Inna Sovsun, a member of the Ukraine parliament, tweeted: “Hey @Twitter, @TwitterSupport, please block the account of the @RussianEmbassy for calling for murder and genocide of Ukrainians.
“It probably violates your community rules. Or maybe, do you only block Ukrainian accounts?”
Labour MP Chris Bryant added: “This should be illegal. This is calling for war crimes. It is time the UK sent the whole Russian Embassy packing back to Moscow. @trussliz What are you going to do?”
Twitter has since put the Russian Embassy’s tweet behind a warning which admits it violated its rules.
The message says: “This Tweet violated the Twitter Rules about hateful conduct.
“However, Twitter has determined that it may be in the public’s interest for the Tweet to remain accessible.”
Russia said on Friday that Ukraine struck a prison in separatist-held territory with US-made HIMARS rockets, killing dozens of prisoners of war and wounding 75.
The general staff of the Ukrainian armed forces denied it carried out the attack, and accused Russia of shelling the prison in order to falsely incriminate Ukraine of war crimes and to cover up executions.
Russian-backed separatist leader Denis Pushilin was quoted by Russia's Interfax news agency as saying the prison, located in the frontline town of Olenivka, housed 193 people and that there were no foreigners among the detainees.
After Russia took control over the southern port of Mariupol following a months-long siege of the Azovstal steel plant there, many Ukrainian fighters were taken prisoner in Olenivka following their surrender.
The Kyiv government has accused Russia of atrocities and brutality against civilians during the invasion and said it had identified more than 10,000 possible war crimes.
Russia has denied targeting civilians or involvement in war crimes and accused Ukraine of staging them to smear its forces.
The United States and more than 40 other countries agreed on 14 July to coordinate investigations into suspected war crimes in Ukraine, with the bulk of the claims concerning alleged actions by Russian forces and their proxies.
Russia announced plans to investigate war crimes it claimed have been committed by Ukrainian forces.
Moscow has justified its invasion by saying it wants to "denazify" Ukraine and branding some of the paramilitary groups as far-right extremists - a charge they strongly reject.