Kyiv and the self-proclaimed republics in south-eastern Ukraine will exchange POWs no earlier than Saturday, December 27, Vasyl Budyk, an advisor to the Ukrainian deputy defense minister, told Interfax-Ukraine on Friday.

"Most likely, such an exchange will become possible tomorrow as the earliest," he said.

Negotiations on this issue are being held constantly, with the most recent meeting taking place at 03.00 on Friday, he added.