( CNN ) German Chancellor Angela Merkel said Saturday that prospects for peace in Ukraine are `` uncertain '' following talks with Russian President Vladimir Putin . Merkel and French President Francois Hollande met with Putin in Moscow on Friday . On Saturday , at the annual Munich Security Conference , she said it is uncertain whether their talks were successful , but it was worth trying . She defended borders in Europe as `` inviolable . '' Russia has shown disrespect for peace and territorial integrity , she said , and Moscow 's actions in Ukraine stand in stark contrast to their commitments . Changing borders by force is out of line with peace and security , and risks escalation , she said . The French , German and Russian leaders met to begin drawing up a new proposal to end the bitter conflict in eastern Ukraine . The peace talks lasted into early Saturday . The parties will engage in further talks by phone on Sunday , the Kremlin said . `` We want to shape security with Russia , not against it , '' Merkel said . U.S. Vice President Joe Biden , addressing the conference after Merkel , said it was time for Russia not to just agree to peace -- referring to a September ceasefire between Ukraine and pro-Russian separatists that was agreed in Minsk , Belarus -- but to act on it . `` Too many times , President Putin has promised peace and delivered tanks , troops and weapons , '' Biden said , restating Western assertions about Russia 's involvement in the conflict . `` We believe we should attempt an honorable peace . We also believe the Ukrainian people have the right to defend themselves , '' Biden said , drawing robust applause . Russian Foreign Minister Sergey Lavrov told the conference that his country `` will be committed to peace . '' `` We are against combat . We would like to see a withdrawal of heavy weapons , '' Lavrov said . He called for `` a direct negotiation '' between Ukrainian government leaders and separatist leaders in Donetsk `` within the framework of territorial integrity . '' Lavrov said talks will continue , adding , `` We believe that there are good grounds for optimism to issue recommendations for conflict resolution . '' The new diplomatic push comes as a worsening conflict in eastern Ukraine is taking an increasingly heavy toll on civilians . Merkel made clear that she would not do a deal with Russia that bypasses Ukraine 's leadership , saying she `` will not decide anything over the heads of anyone . '' The solution must be in line with the Minsk agreement , she said . Russia , Ukraine and separatist leaders signed that pact , but continued fighting has left it in shreds . It 's not yet clear how the new proposal differs from the Minsk agreement . Hollande said Thursday that the joint proposal for new negotiations would be `` based upon the territorial integrity of Ukraine . '' The pair hope the proposal will be acceptable to all parties in the conflict , he said . But he said that `` the option of negotiation , of diplomacy , can not be extended indefinitely . '' Merkel is scheduled to meet with U.S. President Barack Obama in Washington on Monday to discuss , among other topics , Ukraine . Western leaders and Kiev accuse Russia of fostering the conflict by providing weapons and training to the pro-Russian separatists battling Ukrainian forces in the Donetsk and Luhansk regions , as well as sending regular Russian troops over the border to fight . Moscow denies the allegations . Civilians increasingly are falling victim to the violence in Ukraine , with at least 224 killed and more than 540 injured in the final three weeks of January , the U.N. High Commissioner for Human Rights said this week . CNN 's Brian Walker , Jason Hanna , Matthew Hoye and Hande Atay contributed to this report .
Merkel and French President Francois Hollande met with the Russian leader in Moscow . She defended borders in Europe as `` inviolable '' Biden : `` Too many times , President Putin has promised peace and delivered tanks ''