Leonid Kuchma, Ukraine's representative in the Trilateral Contact Group, said he believes a lot of work has been done on the issue of verification of lists for prisoner exchange, but representatives of some areas of the Donetsk and Luhansk regions do everything to delay the process.

"I believe we have done a lot of work on verification. Our people should be thanked, especially the ombudsman. We differ on one issue - the 160 people who are now free - they said they will not go to the territory uncontrolled by Kyiv. And if the team went 14,000 kilometers to all prisons and received a signature from every person on the list stating their unwillingness to return, we cannot come to free people and demand that they write an application, and the Donetsk and Luhansk party is using that to delay the process and not to release our people," Kuchma told reporters in Kyiv on Wednesday, responding to a question from Interfax-Ukraine.

He also mentioned the statement by Ukrainian ombudsman Valeria Lutkovska on readiness to inspect the Ukrainians' living conditions in some areas of the Donetsk and Luhansk regions.

"Our ombudsman said she is ready to visit those prisons and see how our 128 people are doing there, in what conditions they now live. But her request was declined," Kuchma said.

At the same time, Kuchma said he is firmly confident that the process of verification and prisoner exchange will be successfully completed.

Responding to a question about the possible timeframes of achieving accord on this issue, Kuchma said: "Regarding this situation generally, no one can ever say when all this will end."

According to earlier reports, Ukraine verified the lists of prisoners in the period between April 28 and May 12. In that period of time, the group travelled over 14,000 kilometers and its representatives visited 20 regions of Ukraine and 37 penitentiary establishments.