With last summer's cease fire agreement a distant memory, and amid a growing division between the US and Europe on whether to supply the Kiev government with weapons, western leaders are meeting in Munich to desperately find a formula that would stop the escalating fighting in eastern Ukraine.

The Ukraine government claims that Russian tanks and troops are assisting separatist rebels in their drive to defeat government forces and establish a separate country for the largely ethnic Russians who live there. The Ukraine government refuses to bargain away their territory and Russia appears just as determined to help the rebels win. The fighting is becoming fiercer and the government in Kiev says it needs arms to push back against the Russian backed rebel drive.

But Germany and France oppose sending weapons to Kiev, thinking that it would only escalate an already tense situation - perhaps even leading to Putin sending in regular Russian troops. But a recent meeting in Minsk with Putin and German and French leaders failed to reach an agreement to calm the situation.

Reuters:

The leaders of Russia, Ukraine, Germany and France agreed to meet in Belarus on Wednesday to try to broker a peace deal for Ukraine amid escalating violence there and signs of cracks in the transatlantic consensus on confronting Vladimir Putin.

The four leaders held a call on Sunday, two days after Chancellor Angela Merkel and French President Francois Hollande traveled to Moscow for talks with Putin that produced no breakthrough in the nearly year-long conflict that has claimed over 5,000 lives.

After the call, Ukraine President Petro Poroshenko said progress had been made and that he was hopeful the meeting in Minsk would lead to a "swift and unconditional ceasefire" in eastern Ukraine, where pro-Russian separatists have stepped up a military offensive in recent weeks, seizing new territory.

A Ukraine military spokesman said on Sunday that intense fighting was continuing around the rail junction town of Debaltseve, with rebel fighters making repeated attempts to storm lines defended by government troops.

At a high-level security conference in Munich over the weekend, Merkel said it was uncertain whether further negotiations would lead to a deal with Putin but argued that all opportunities for a diplomatic solution should be pursued.

She came under sharp criticism from U.S. senators Lyndsey Graham and John McCain, both Republican hawks, for opposing the sending of defensive weapons to the Ukraine army to help it fight the separatists.

"The Ukrainians are being slaughtered and we're sending them blankets and meals," McCain said in Munich. "Blankets don't do well against Russian tanks."

U.S. Secretary of State John Kerry sought to play down the differences with Europe.

"Will we remain united? The answer is absolutely, positively, unequivocally we are united, we will remain united," Kerry told the conference on Sunday, describing any differences as tactical rather than strategic.

Members of the Obama administration are also believed to be skeptical about arming Ukraine but the president faces intense pressure from a Republican-led Congress to act.

The Germans believe sending weapons to a depleted Ukraine army would not improve its chances against separatists armed with "unlimited" supplies of Russian military equipment.

They also fear that delivering arms would internationalize the conflict, playing into the hands of Putin, who has painted the crisis as a western plot to weaken Russia.

Putin is in the driver's seat and would almost certainly counter any effort to supply the Ukrainian army with weapons by increasing Russian assistance. Nor will the Russian president make a deal that in any way weakens the position of the rebels. He doesn't have to. The Russian/rebel coalition is making progress against the undermanned, under supplied Ukrainian army and while government forces are giving a good account of themselves, there is no doubt they are being pushed back.

The bottom line: Neither the US or Europe will go to war against Russia to save Ukraine. As long as Putin can maintain the fig leaf of Russian non-involvement and the rebels keep advancing, the Russian president isn't likely to do anything that would antagonize the west to the point where they would intervene.