On Saturday, Russia's top diplomat, Sergei Lavrov, accused the West of seeking a regime in Moscow.

"The West is showing unambiguously that they do not want to force [Russia] to change policy. They want to achieve a change in regime, " he said while attending a meeting on foreign and defense policies in Moscow.

Lavrov was responding to US Vice President Joe Biden's statement in Ukraine on Friday, hinting at possible further sanctions on Russia in protest of its role in Ukraine. Both the US and the European Union imposed several rounds of sanctions on Russia this year, affecting the country's energy, defense and finance sectors.

Following Biden's visit at the beginning of the weekend, Ukraine received military assistance from the US, which included radars and other "non-lethal" assistance such as night vision goggles and safety vests.

NATO refused all kinds of arms and artillery assistance to Ukraine, despite Kyiv's defense minister, Stepan Poltorak, claiming that Russia had stationed thousands of troops to Kyiv's east and that "the presence of 7,500 representatives of Russian armed forces in Ukraine" destabilized the situation.

The news agency AFP also quoted Ukraine's head of security as saying that 20 units of Russian military equipment had crossed the border on Saturday towards Luhansk, a rebel stronghold where fighting in the past 24 hours killed four Ukrainian soldiers and one civilian.

More than 1,000 people have died in spite of the ceasefire between Russia and Ukraine came into effect in September. According to the United Nations, nearly 4,300 people have died since the conflict began in March this year, including 298 passengers aboard the MH17 which was shot down in July.

mg/kms (AFP, dpa)