Kiev:
Separatist rebels killed seven Ukrainian soldiers in a bloody ambush in the restive east yesterday, rattling efforts by Europe to step up a diplomatic push to resolve the escalating crisis on its doorstep.
The violence flared as German Foreign Minister Frank-Walter Steinmeier was in Ukraine to push Kiev and pro-Moscow rebels to come together at the negotiating table after the East-West security body OSCE drew up a roadmap aimed at easing tensions.
But the battle lines remained drawn, with fears that Ukraine could be threatened with collapse following weekend independence referendums in the eastern industrial provinces of Donetsk and Lugansk that have been rejected by Kiev and the West.
Russia, despite expressing support for the "extremely important" roadmap, said Kiev must halt its military operation in the east if rebels are to comply with the peace initiative.
And it accused Ukraine's pro-West authorities of refusing "real dialogue" with the separatists.
The Organisation for Security and Cooperation in Europe, which began life as a forum for East-West dialogue in the Cold War, said the initiative focuses on "restraint from violence, disarmament, national dialogue, and elections".
Kiev is hosting a round table meeting on Wednesday involving the government, parliament and regional leaders but notably not any separatist representatives.
On the ground, the Ukrainian military suffered one of its bloodiest single days since the separatist insurrection in the east erupted.
Kiev said seven soldiers were killed in an ambush by rebels armed with heavy weapons between the insurgent strongholds of Slavyansk and nearby Kramatorsk, bringing to 16 the number killed since mid-April.
Rebels in Lugansk claimed their self-styled governor Valery Bolotov survived an "assassination attempt" today after assailants opened fire on his car with automatic rifles.
Violence has raged for weeks in eastern Ukraine as government troops carry out what it describes as "anti-terrorist" operations against well-armed rebels who seized cities and towns in the chaos that followed the ouster of Ukraine's pro-Russian leader Viktor Yanukovych in February.
Interim President Oleksandr Turchynov insisted yesterday that the offensive would continue despite the Kremlin's demands.