A ceasefire deal for Ukraine is in limbo after international talks only highlighted disagreement over the plan, and Washington accused Moscow of lying about its role in the country's conflict.
Russian-backed rebels in eastern Ukraine insisted on Tuesday they were pulling back heavy artillery from the frontline, in accordance with a truce agreed in Minsk on February 12th.
Ukraine’s military spokesman Andriy Lysenko said Kiev’s forces could not withdraw artillery, however, because they were still under rebel fire in several areas.
Col Lysenko said the militants were “just relocating and re-grouping, using the cover of a heavy-weapons pullback. The information from militants on withdrawing heavy weapons is not true.”
“As soon as there is a ceasefire for two days, that is the signal to start a withdrawal,” he added.
After a meeting in Paris of the Ukrainian, Russian, German and French foreign ministers, Germany’s Frank-Walter Steinmeier said the situation in eastern Ukraine was “extremely fragile” after repeated ceasefire violations, and he described the lack of trust between Kiev and Moscow as “total”.
Ukraine is furious that the rebels – allegedly backed by unmarked Russian army units – seized the strategic transport hub of Debaltseve after the supposed start of the ceasefire.
Moscow insists the Minsk deal did not give Kiev control of the town, and the rebels claim they are now implementing the truce, despite allegedly coming under Ukrainian fire.
"Unfortunately, there was no political agreement on how to condemn what happened in Debaltseve," Ukraine's foreign minister Pavlo Klimkin said after the Paris talks.
"We are extremely concerned by recent attacks in the vicinity of Mariupol … We are concerned by a possible relocation of forces from Debaltseve in the direction of Mariupol," he added.
Mariupol is a major government-controlled port in southern Donetsk region, which militant leaders insist should be part of their territory under any peace deal. Fighting has continued close to the city, and Ukraine claims Russia has sent dozens more tanks over the border to reinforce rebels in the area.
In perhaps his most blunt criticism of Moscow's role in the Ukraine conflict, US secretary of state John Kerry said "Russia is engaged in a rather remarkable period of the most overt and extensive propaganda exercise that I've seen since the very height of the Cold War."
Mr Kerry told a US Senate subcommittee that top Russian officials “have been persisting in their misrepresentations, lies, whatever you want to call them about their activities there to my face, to the face of others on many different occasions.”
The White House is under growing domestic pressure to send defensive weapons to Ukraine, but president Barack Obama has so far opposed such a move, as have major EU nations including Germany and France.
Lithuania and Poland – close allies of Ukraine and near neighbours of Russia – have suggested they may supply arms to Kiev, which on Tuesday announced a deal to buy unspecified weapons from the United Arab Emirates.
Britain's prime minister David Cameron revealed yesterday that in the next month London would deploy "British service personnel to provide advice and a range of training, to tactical intelligence to logistics, to medical care," to Ukraine, and develop an "infantry training programme" with the country.
“If we don’t stand up to Russia, in the long-term it will be deeply damaging to all of us because you’ll see further destabilisation. Next it’ll be Moldova or one of the Baltic states,” Mr Cameron added.
Moscow denies destabilising Ukraine and called the Paris talks “very useful”, while rejecting calls for tighter international monitoring of the Russia-Ukraine border.
