KIEV, Aug. 4 - Russia cannot introduce its peacekeeping troops in Ukraine unilaterally, said Andriy Lysenko, a spokesman for the Ukrainian National Security and Defense Council.

"The introduction of peacekeepers is the strict prerogative of the UN (United Nations) Security Council. If a decision is made to introduce peacekeepers to any part of Ukraine, there should be a condition: it must be accepted by both parties to the conflict. So far there has been no UN statement, no consent from either party," Lysenko said at a Monday briefing.