"We know for sure who has been blocking – this is Russia that backs the militants," he told RFE/RL.

According to him, the Ukrainian government is considering different additional measures to end the Donbas war. "If the Minsk agreements have not brought peace over the three years, maybe there is some additional leverage that we must use to let our people live in peace. That's why we are talking about peacekeeping forces in any format ... The option of equipping an OSCE mission (the current or a new one) with small arms was discussed, so that they could feel more confident and visit those places they should. Another option is a UN peacekeeping mission," he said.

Read alsoNormandy Four leaders issue joint statement following phone talksEarlier, Russian Foreign Ministry spokeswoman Maria Zakharova labeled Ukraine's initiative to deploy UN peacekeepers in the Donbas conflict zone as an attempt to thwart the implementation of the Minsk II peace agreements.

As UNIAN reported earlier, Ukrainian President Petro Poroshenko announced at a UN General Assembly session on August 22 that Ukraine would come up with an initiative in autumn to deploy UN peacekeepers in uncontrolled areas in Donbas.