Reportedly, Russians executed nine captured Ukrainian troops in the Kursk border region.

“We have also written to the United Nations and the Red Cross about these executions. Moscow is breaching all the rules and customs of war,” a Ukrainian official said.

Kyiv has deployed thousands of troops into the Russian border region since it launched its shock incursion earlier this summer.

A video of the Ukrainian soldiers had also gone viral in which the troops can be seen stripped to their underwear and lying face down in what appeared to be farmland in Kursk.

Ukraine has frequently accused Russia of executing captured Ukrainian troops - a war crime under the Geneva Convention.

Earlier, Ukraine alleged that Russian forces had executed 93 Ukrainian soldiers since the beginning of the conflict.