Has Putin reached his limit on his willingness to intervene in Ukraine?

Putin said that he would hold Poroshenko responsible for new bloodshed in the east, but he appears disinclined to become more involved in Ukraine's conflict.

As eastern Ukraine descended into all-out war on Tuesday – including what Russian media describe as a "tank battle" near the village of Karlivka – following the lifting of a ten-day ceasefire, Vladimir Putin warned that he would hold Ukrainian President Petro Poroshenko personally accountable for the consequences.

"Regrettably, President Poroshenko took a decision to resume combat operations, and we – I mean myself and my colleagues in Europe – have failed to persuade him that a path to lasting, sustainable peace cannot be through war. Until now, [Poroshenko] had nothing to do with orders to begin military actions, but now he has taken full responsibility upon himself – not only military but also political responsibility, which by far is more important," President Putin told a meeting of Russia's top diplomats in Moscow Tuesday.

Putin said that he had reached agreement on the need to extend the ceasefire and press forward with peace talks with German Chancellor Angela Merkel and French President François Hollande in a late night telephone conversation that also included Mr. Poroshenko.

"We need some kind of insurance net around all of Europe so that the Iraqi, Libyan, Syrian – and unfortunately we have to mention the Ukrainian – scenarios do not become a contagious disease," he added.

Split opinions

Putin has not always been on the same page with his European colleagues about Ukraine, and it's only been a few days since the official Russian media was seething furiously over Kiev's decision to sign an economic association agreement with the European Union.

But the Kremlin has made conciliatory gestures, especially over the past week, that suggest it might be interested in a negotiating process that could lead to peace. A week ago Putin had the Russian parliament cancel a resolution granting him special powers to use military force in Ukraine, and he did give Moscow's backing to Poroshenko's ceasefire and tentative talks between Kiev and the rebels.

While Kiev, backed by Washington, has maintained that Russian interference is the main cause of east Ukraine's rebellion, Russia has insisted that it has nothing to do with it. Neither narrative can be completely true.

A Gallup poll released in early June illustrates how deeply Ukrainians remain divided, with majorities in the east expressing distrust of the US, opposition to integrating economically with the EU and unwillingness to make sacrifices for the sake of economic reform. Earlier polls showed that large majorities in east Ukraine regard the interim government in Kiev as "illegitimate."

"In the last eight, nine years when we collect data in Ukraine, we see it all the time on most of the aspects of life actually. Any political situation we ask of the country, even economics in the country, the split between different regions and between different ethnic groups existed for years, and the government didn’t pay attention to it," Gallup pollster Neli Esipova told Voice of America.

On the other hand, Kremlin denials that Russia has been stirring the pot in east Ukraine ring hollow. Ukrainian rebel leaders have held regular consultations in Moscow, and Russia does not deny sending "aid" to strife-torn Donetsk and Luhansk. Other evidence suggests that Moscow has permitted a steady stream of "volunteers" as well as military equipment to reach the rebels across the Russo-Ukrainian border.

A middle road for Putin?

Some experts say Putin faces internal opposition from pro-war forces who think he should be more assertive in supporting east Ukraine's beleaguered rebels.

"Everybody wonders why Putin isn't using troops [to back the rebels]," says Sergei Markov, director of the pro-Kremlin Institute of Political Studies and a frequent Kremlin adviser. "But Putin does understand how hard the war is, and wants to do what he can to preserve peace."

Alexei Makarkin, director of the independent Center for Political Technologies, says that Putin's recent shift toward a negotiated solution suggests that he recognizes that Ukraine has slipped out of Russia's sphere of influence forever, and that he must try to salvage what he can of Moscow's badly shredded relationship with the West.

Putin told the meeting of diplomats that Russia will not "wind down" its ties with the US, though he admitted that they have been "spoiled" by the Ukraine crisis.

"Putin's attitude toward the West is hardly positive, but he understands that Russia lacks reserves" to stand up to Western pressures, says Mr. Makarkin. "Basically, Putin is treading a very fine line. He has to find ways to defend Russian interests without landing in a full-scale confrontation with the West."