Agreement on Ukraine could be reached by Friday
President Vladimir Putin outlined plans for a ceasefire in eastern Ukraine but Ukraine's prime minister dismissed the proposal, while France expressed its disapproval of Moscow's support for separatist forces by halting delivery of a warship.
After speaking to Ukrainian President Petro Poroshenko by phone, Putin said he believed Kiev and pro-Russian separatists could reach agreement at planned talks in Minsk on Friday.
"Our views on the way to resolve the conflict, as it seemed to me, are very close," Putin told reporters during a visit to the Mongolian capital of Ulan Bator, describing the seven steps he had put forward to secure a resolution to the crisis.
They included separatists halting offensive operations, Ukrainian forces pulling back, an end to Ukrainian air strikes, the creation of humanitarian aid corridors, the rebuilding of damaged infrastructure and prisoner exchanges.
Poroshenko indicated the conversation with Putin had injected some momentum into efforts to end a conflict that has killed more than 2,600 people since April, saying he hoped the "peace process will finally begin" at Friday's talks and that he and Putin had a "mutual understanding" on steps towards peace.
But Prime Minister Arseny Yatseniuk dismissed the plan as a "deception" on the eve of a NATO summit that will discuss Ukraine, adding in a harshly worded statement: "The real plan of Putin is to destroy Ukraine and to restore the Soviet Union."
US President Barack Obama also voiced caution, saying the conflict could end only if Russia stopped supplying the rebels with weapons and soldiers, a charge Moscow has denied.
Visiting the former Soviet republic of Estonia, now in NATO and the European Union, Obama said previous ceasefires had not worked "either because Russia has not been serious about it or it's pretended that it's not controlling the separatists".
In a further sign of the West's growing mistrust and disapproval of Moscow over its conduct in Ukraine, France said it would not go ahead with the planned delivery of the first of two Mistral helicopter carriers to Russia.
Moscow has said scrapping the €1.2bn deal would harm France more than Russia and the Defence Ministry described the decision as "no tragedy", but the move is likely to anger the Kremlin and underlines Russia's growing isolation over events in Ukraine.