Russia urged Ukraine's leaders on Wednesday to talk directly to separatists to end the conflict in the east, but Kiev rejected the call and told Moscow to stop "playing games" aimed at legitimizing "terrorists."
Kiev and the West accuse Russia of destabilizing Ukraine by providing the rebels with money, arms and reinforcements. The West has imposed sanctions on Moscow over the conflict in which more than 4,000 people have been killed since mid-April.
Russia backs the separatists but denies it is directly involved in the conflict in the Donbass region.
"We are calling for the establishment of stable contacts between Kiev and Donbass representatives with the aim of reaching mutually acceptable agreements," Russian Foreign Minister Sergei Lavrov said in a policy address to the lower house of parliament in Moscow.
But Ukrainian Prime Minister Arseniy Yatsenyuk hit back, accusing Moscow of trying to push Ukraine into recognizing the pro-Russian rebels who are fighting government troops to split parts of the eastern Donetsk and Luhansk regions from Kiev.
Speaking at a government meeting, he declared Kiev would not speak directly to the separatists and repeated the phrase slowly in Russian for emphasis, saying: "We will not hold direct talks with your mercenaries."
A cease-fire was agreed on Sept. 5 in the Belarussian capital of Minsk as part of a wider deal between Moscow, Kiev and the rebels under the auspices of the Organization for Security and Cooperation in Europe (OSCE) — with a former president representing Kiev to avoid formal recognition of the rebels.
But the truce is under constant pressure, with deaths of government troops and civilians reported daily. Kiev and the West accuse Russia of sending tanks and troops to back the rebels but Moscow denies the charges.
Lavrov and president Vladimir Putin held talks with German Foreign Minister Frank-Walter Steinmeier in Moscow on Tuesday but failed to overcome deep rifts over Ukraine.
Yatsenyuk called on Moscow to "stop playing games aimed at legitimizing bandits and terrorists."
"If you [Russia] want peace — fulfill the Minsk agreement," he said.
Lavrov said in Moscow that the "party of war" — supporters of Kiev's military campaign against the rebels — had tried to exclude the separatists from peace moves and to "force the West to seek the consent of Russia to act as a side in the conflict."
"This is a completely counter-productive and provocative line that has no chance of succeeding," Lavrov said.