Berlin: The foreign ministers of Russia, Ukraine, Germany and France met on Wednesday seeking to defuse the conflict in Ukraine, whose president charged that Moscow sent in 9,000 troops to fuel the separatist insurgency.
The talks in Berlin got underway against the unpromising backdrop of fresh clashes between Ukrainian government forces and pro-Moscow rebels in the east of the former Soviet republic.
As violence flared, German Foreign Minister Frank-Walter Steinmeier warned that "the population is paying the price".
Hopes were muted that the four top diplomats could agree any major steps toward ending the conflict, or set a date for a hoped-for peace summit in Kazakhstan, after their previous Berlin meeting on January 12 ended without substantial progress.
"I don`t want to raise huge expectations" of a diplomatic breakthrough, German Chancellor Angela Merkel said before the talks got underway.
"It appears the ceasefire is becoming ever more brittle," she added.
Steinmeier appealed to all sides "to negotiate in a constructive way so we can reach the goal that eluded us last Monday and will lead hopefully not just to a ceasefire but to key steps toward implementing the Minsk agreement".
Days of heavy fighting centred around Donetsk`s ruined airport have left in tatters the already shaky truce deal agreed in Belarus in September. At least six people were killed Wednesday across separatist-controlled regions of Ukraine`s industrial southeast.
US Secretary of State John Kerry accused the rebels of attempting "a blatant land grab", calling their recent incursions "an effort to try to broaden the amount of territory that is being held".
Ukrainian President Petro Poroshenko, speaking earlier at the World Economic Forum in Davos, said the upsurge in fighting after a nearly month-long lull was prompted by a new infusion of Russian forces and weapons.
"We have more than 9,000 troops of the Russian Federation on my territory, including more than 500 tanks and heavy artillery and armed personnel carriers," the pro-Western leader claimed.
Repeated rounds of applause broke out at the Swiss forum during an emotional address that saw Poroshenko, a 49-year-old former chocolate baron, hold up a fragment of a bus in which 13 civilians died after it was hit by an alleged rebel-fired rocket last week.
"Terror is not the problem of Ukraine, and even not the problem of Europe," Poroshenko told the high-powered audience in English. "This is a global problem."
Ukraine on Tuesday alleged that Russian regular forces had attacked its troops in Lugansk after crossing over into the separatist region the day before.
Moscow strongly denies supporting the insurgents despite NATO satellite imagery purporting to show its forces` presence in Ukraine -- photographs Russia claims were either doctored or misinterpreted by the Western military bloc.
"As for the charges of us supplying troops and weapons -- we hear this all the time," Russian Foreign Minister Sergei Lavrov said in Moscow.
"And each time, I say: if you are so sure about this, show us the proof ... But the proof -- they either do not want to present it or simply cannot."
A top US general -- in Kiev to help bolster Ukraine`s NATO ties -- said evidence was "very clear" of Russia doubling the amount of modern military equipment available to the militias in recent weeks.
"If you don`t believe that that`s being provided by Russia, then you do not want to believe," said US Army Europe commander Ben Hodges.Ukraine`s severe financial crisis has been worsened by extra war spending and the eastern region`s industrial collapse.
In Davos, IMF head Christine Lagarde said Poroshenko has asked for a new and broader rescue package, adding that "we will consult with the IMF Executive Board on the authorities` request".
Compounding Ukraine`s problems last year was a months-long cut off from Russian gas supplies.
Kiev accused Moscow of using gas as a means of "economic aggression" and refused to pay the higher rates Russia slapped on Ukraine in the wake of last February`s ouster of a Kremlin-backed president.
Poroshenko said Wednesday that Ukraine had in the past year halved the amount of gas it imported from Russia.
He vowed to completely break Ukraine`s energy dependence on Russia by 2017 with the help of a transition to western European imports and his country`s own shale gas supplies.
"I am absolutely sure that in two years` time, we will be absolutely energy independent from Russia," said Poroshenko.