The leaders of Russia, France and Germany have agreed in Moscow to work on a peace blueprint they will put to Ukraine's President on Sunday.
Russian President Vladimir Putin, French President Francois Hollande and German Chancellor Angela Merkel talked more than four hours on Friday.
All three parties described the meeting as "constructive and substantive". They will discuss the plan for eastern Ukraine by phone with President Petro Poroshenko on Sunday.
The plan is thought to be an attempt to revive a September ceasefire, signed in Minsk in Belarus. Since then the rebels have seized more ground, raising alarm in Kiev and among Ukraine's backers.
There was no joint press conference or statement from the Russian, German and French leaders after such a high-profile Kremlin meeting. Chancellor Merkel and President Hollande left for the airport straight away.
The three sides said that work would continue on a possible blueprint for a deal, based on the French and German initiative, with added proposals from President Poroshenko and President Putin.
Some 1.2 million Ukrainians have fled their homes since last April, when the rebels seized a big swathe of the Luhansk and Donetsk regions following Russia's annexation of Crimea.
Events in Ukraine are also expected to feature prominently at a security conference in the German city of Munich.
Merkel, US Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov are all due to speak at the event.
The peace proposal Hollande and Merkel took to Moscow on Friday was crafted with the Ukrainian government on Thursday.
Hollande said the aim was not just a ceasefire but a "comprehensive agreement" - although Merkel said it was "totally open" whether that could be achieved.