Ukrainian soldiers clash with pro-Russia protesters on the field near Kramatorsk, in eastern Ukraine yesterday. Photo: Reuters

Separatists flew the Russian flag on armoured vehicles taken from the Ukrainian army yesterday, humiliating a Kiev government operation to recapture eastern towns controlled by pro-Moscow partisans.

Six armoured personnel carriers were driven into the rebel-held town of Slaviansk to waves and shouts of “Russia! Russia!”. It was not immediately clear whether they had been captured by rebels or handed over to them by Ukrainian deserters.

Another 15 armoured troop carriers full of paratroops were surrounded and halted by a pro-Russian crowd at a town near an airbase. They were allowed to retreat only after the soldiers had handed over the firing pins from their rifles to a rebel commander.

The military setback leaves Kiev looking weak on the eve of a peace conference today, when its foreign minister will meet his Russian, US and EU counterparts in Geneva.

Moscow has responded to the overthrow of Moscow-backed Ukrainian president Viktor Yanukovych in February by declaring the interim Kiev government an illegitimate gang of fascists. It has also announced its right to intervene militarily across the former Soviet Union to protect Russian speakers, a new doctrine that has overturned decades of post-Cold War diplomacy.

The EU took a step towards imposing tougher economic sanctions on Russia by informing its member states of the likely impact of proposed measures on each of them. To keep the sensitive material from leaking, each of the 28 member states was told only of the expected risks its own economy would face. The information was handed to each EU ambassador in a sealed brown envelope.

Western allies believe that Russian agents are coordinating the uprising

Russia seized and annexed Ukraine’s Crimea peninsula last month, and its armed supporters have now taken control over swathes of Ukraine’s eastern industrial heartland. So far, the US and EU have imposed only targeted sanctions against a list of Russian and Ukrainian individuals and firms, which Moscow has openly mocked.

The Ukrainian government confirmed that six of its armoured vehicles were now in the hands of separatists. Kiev had sent the convoy of paratroops to capture an airfield, the start of an operation to reclaim towns held by separatists who have declared an independent “People’s Republic” in the industrial Donbass region.

The Ukrainian government and its Western allies believe Russian agents are coordinating the uprising. Moscow denies it is involved and says Kiev is precipitating civil war by sending troops to put down the revolt.