Deploying NATO peacekeepers in Ukraine would lead to direct confrontation between Russia and the North-Atlantic Alliance, Moscow warned on Wednesday.
Russia has also taken note of Poland's intention to raise the issue of sending military contingents to Ukraine at the upcoming NATO summit, Foreign Minister Sergey Lavrov said at a meeting with students of the MGIMO University in Moscow.
"I hope they (Poland) understand what they are talking about. This will be the very direct clash of the Russian and NATO armed forces, which everyone not only would like to avoid, but say that it should not take place in principle," said Lavrov.
Lavrov added that if Poland and the Baltic countries -- Estonia, Latvia, Lithuania -- send troops to Ukraine separate from NATO, these countries would face the consequences of directly entering the conflict.
He also claimed that Poland, after entering Ukraine under such a peacekeeping mission, might seek to separate western Ukraine from the rest of the country and remain there permanently.
"Polish representatives are known for their non-standard moves," added the official, accusing Warsaw of seeking to provoke "big trouble."
"I do not exclude that when they talk about peacekeepers, they probably mean (deploying troops) on their borders -- the west of Ukraine. Maybe they want to introduce peacekeepers, make headquarters in Lviv, then stay there. They had such thoughts -- and not only thoughts. It was in the past," Lavrov said.
Criticizing calls to give Ukraine MiG fighter jets and man-portable air-defense systems (MANPADS), Lavrov said such arms could fall into wrong hands and spread through Europe, posing a threat for all countries.
The minister said peace talks between Russian and Ukraine continued with difficulty, accusing the Ukrainian side of constantly changing its positions.
He suggested that Kyiv was biding time at the US' instruction, claiming that Washington wanted to draw out the conflict for Russia.
"It is difficult to get rid of the impression that Kyiv is held by the American colleagues. Both our and Western political scientists say Americans simply assume that it is not profitable for them to complete this process quickly. Apparently, they want to keep us in a state of combat for as long as possible," he said.
At least 953 civilians have been killed during the war and 1,557 injured, according to UN estimates.
However, the international body has warned that the true toll is likely to be "considerably higher."
More than 3.5 million people have fled Ukraine amid the Russian attacks, according to the UN refugee agency.