French President Emmanuel Macron and his Russian counterpart Vladimir Putin are set to held a phone call in the latest effort to defuse tensions over Ukraine.
The conversation, scheduled to take place on Sunday, will mark the fifth time the two leaders talk since the start of the year.
The move comes as diplomatic efforts to avert a war in Eastern Europe struggle to make a breakthrough.
On Saturday, the OCSE European security body reported at least 2,000 ceasefire violations in eastern Ukraine.
International monitors also corroborated reports of a civilian casualty in government-controlled Marinka in the Donetsk region.
Two Ukrainian soldiers died amid the shelling, authorities reported on Saturday.
Russian media said the separatist regions of Donetsk and Luhansk have reported “the most intensive shelling” by Kyiv in recent months.
The pro-Russian rebels also declared general mobilisations in the two areas, calling up men to fight even as they announced the mass evacuations of women and children.
While Putin insists that he has no intention to invade Ukraine, the Russian leader oversaw nuclear drills involving hypersonic ballistic missiles on Saturday.
US President Joe Biden, who earlier said he was “convinced” Russia would invade in the coming days, is convening a rare Sunday National Security Council meeting over the crisis.
US and EU officials have said they believe Moscow is attempting to fabricate a pretext for its offensive by having proxy outlets put out false information about violence in rebel-held enclaves.
Speaking to Macron on Saturday, Ukrainian President Volodymyr Zelenskyy said he would not respond to Russia’s provocations, according to the Elysee.
But in his speech to the Munich Security Conference, he also condemned “a policy of appeasement” towards Moscow.
“For eight years, Ukraine has been holding back one of the greatest armies in the world,” he said.
He called for “clear, feasible timeframes” for Ukraine to join the US-led NATO military alliance – something Moscow has said is a red line for its security.