"The President stressed the need to intensify the PACE’s efforts to release the Ukrainian hostages held by the terrorists,” the press service said in a statement.

“According to the president, currently, more than 600 Ukrainian citizens are in captivity, despite clear agreements being reached in Minsk [on their release]," the statement goes on.

The parties also agreed that the Minsk agreements need to be unconditionally and immediately fulfilled, as they are recognized by all parties to the conflict, and this being the only way to resolve the situation peacefully, the press service said.

In addition, Brasseur expressed on behalf of the PACE her condolences to the Ukrainian people in connection the tragedy near Volnovakha, when a Grad rocket, which is thought to have been fired by Russian-backed militants, exploded near a bus, killing 13 people.

As UNIAN reported earlier, as of December 25, 684 people were held captive by militant groups in the Donbas, according to the data of the Security Service of Ukraine. 

On December 26, a prisoner exchange took place in the ATO area, with 146 Ukrainians being released.

The risoner exchange agreement was reached during negotiations of the tripartite contract group to resolve the situation in the Donbas that were held in Minsk on December 24.

On December 27, three soldiers of the 80th airmobile brigade and one volunteer, and later four more prisoners - one military and three civilians - were freed from the militant’s captivity without exchange.