"We need a little patience. Everything is due to be clarified and resolved in the course of the day," said Novikov who represents Ukrainian national Nikolai Karpyuk who was sentenced to 22.5 years behind bars in Russia for taking part in armed clashes in Chechnya as a gang member. At least 30 military servicemen were killed in them.

For its part, the office of Ukrainian President Vladimir Zelensky has refuted media reports saying that the process of mutual exchange of detainees between Moscow and Kiev had been completed. "The process of the mutual release of detained individuals continues. Reports asserting that it has been completed are not true. When the mutual release of detainees is over, the president’s office will inform about that through official channels," Zelensky’s office said in a Facebook post.