The United Nations on Monday warned that Russian forces have been killing more captured Ukrainian soldiers over recent months, echoing growing allegations from officials in Kyiv.
Moscow and Kyiv have accused each other of committing war crimes, including killing prisoners of war, since Russia invaded Ukraine in February 2022.
The United Nations monitoring mission in Ukraine said that since the end of August last year it had "recorded 79 such executions in 24 separate incidents" by Russian forces.
"These incidents did not occur in a vacuum. Public figures in the Russian Federation have explicitly called for inhumane treatment, and even execution, of captured Ukrainian military personnel," said Danielle Bell, head of the mission.
"Combined with broad amnesty laws, such statements have the potential to incite or encourage unlawful behaviour," she added in the statement.
The statement also said that the mission had recorded one execution by the Ukrainian armed forces of a "wounded and incapacitated" Russian soldier last year.
Referring to the killings by Russian forces, Ukrainian foreign minister Andriy Sybiga suggested, without providing evidence, that they could constitute "one of the largest campaigns of intentional POW murder in modern history".
"The world must not only condemn, but also take urgent action. We need new and effective international legal tools, and concrete steps to hold the perpetrators accountable," he said in a post on social media.
Ukrainian human rights ombudsman Dmytro Lubinets routinely announces that he has called on the UN and International Committee of the Red Cross to investigate evidence of killings of captured Ukrainian soldiers.