Germany's Angela Merkel said on Saturday that providing arms to help Ukraine fight pro-Russian separatists would not solve the crisis there, drawing sharp rebukes from U.S. politicians who accused Berlin of turning its back on an ally in distress.
The heated exchanges at a security conference in Munich pointed to cracks in the transatlantic consensus on how to confront Russian President Vladimir Putin over a deepening conflict in eastern Ukraine that has killed more than 5,000.
Ukraine's military said on Saturday that pro-Russian separatists had stepped up shelling of government forces and appeared to be amassing troops for new offensives on the key railway town of Debaltseve and the coastal city of Mariupol.
The rebel offensive has triggered a flurry of shuttle diplomacy, with Merkel and French President Francois Hollande jetting to Moscow on Friday to try to convince Putin to do a peace deal.
But European officials acknowledge that the Russian leader may have little incentive to negotiate now, preferring to sit back and watch as separatists seize more territory, undermining a ceasefire agreement clinched last September in the Belarus capital Minsk.
The German leader conceded in Munich that it was uncertain whether a Franco-German peace plan presented to Kiev and Moscow this week would succeed.
But she rejected the notion that sending weapons to Kiev, an idea being considered by U.S. President Barack Obama, would help resolve the conflict.
"I understand the debate but I believe that more weapons will not lead to the progress Ukraine needs. I really doubt that," said the conservative German leader, who has led western efforts to try to resolve the crisis through negotiations and will travel to Washington on Sunday for talks with Obama.
Blankets Vs Tanks
U.S. senators Lyndsey Graham and John McCain, two Republican hawks who attended the conference, were withering in their criticism of the German stance, which is supported by other big European countries like France.
"At the end of the day, to our European friends, this is not working," Graham said of Merkel's diplomatic efforts. "You can go to Moscow until you turn blue in the face. Stand up to what is clearly a lie and a danger."
McCain added: "The Ukrainians are being slaughtered and we're sending them blankets and meals. Blankets don't do well against Russian tanks."
U.S. Vice President Joe Biden, also speaking in Munich, tried to play down differences with Europe, saying he and Obama agreed that no efforts should be spared to resolve the conflict peacefully.
But he made clear that Washington stood ready to provide Ukraine with the means to defend itself, saying: "Too many times President Putin has promised peace and delivered tanks, troops and weapons."