Adviser to the SBU chairman Yurii Tandit announced on 112 Ukraine TV channel, Censor.NET informs.
"At the last moment, when Kovalchuk departed to Donetsk, some difficulties occured. We understood that the militants were trying to delay the negotiations and cheat us to keep our guys, whom we previously mentioned. It was decided to come back and continue the talks on Monday," Tandit said.
Tandit: Our priority is liberation of captive Ukrainians, so we consider exchange of Russian commandos
He added that the exchange of prisoners, which has been prepared for about three months in the format of "13 to 13", failed at the last moment when the militants raised new requirements.