KIEV - Ukraine is hosting roundtable "national unity" talks on Wednesday after its military suffered its bloodiest day since launching an offensive to oust separatist pro-Moscow rebels in the east.
Insurgents killed seven Ukrainian soldiers in an ambush and firefight near the rebel-held eastern town of Kramatorsk on Tuesday, underscoring the urgency of a new diplomatic push by Europe to resolve the escalating crisis on its doorstep.
European leaders have called for Wednesday's talks in Kiev, being held under a roadmap drafted by the pan-European security body the OSCE, to be as inclusive as possible.
The meeting, due to start at 1330 GMT, will bring together government officials including Prime Minister Arseniy Yatsenyuk as well as lawmakers, and former leaders and candidates running in this month's crunch presidential election.
But separatist rebels who have overrun more than a dozen towns in the east since early April will not be sitting at the table.
"The Ukrainian leadership is open for an inclusive national unity dialogue," a Ukrainian foreign ministry spokesman said.
"However, it is impossible to engage terrorists, whose objective is to destroy not only national unity but Ukrainian statehood," the spokesman said in a statement Wednesday.
He accused Russia of playing a "dirty game" with a "biased" interpretation of the OSCE roadmap, and demanded that Moscow pull back its troops from the border.
German Chancellor Angela Merkel nevertheless said the talks offered a "good possibility" of finding a way out of the worst crisis between Moscow and the West since the Cold War.
"The more representative the roundtables are, the better that is," she said on Tuesday, but added that there was no place for those who support violence.
Her comments came a day after her Foreign Minister Frank-Walter Steinmeier was in Ukraine to push Kiev and pro-Moscow rebels to come together at the negotiating table ahead of the May 25 presidential election.
Wednesday's roundtable discussions, to be moderated by veteran German diplomat Wolfgang Ischinger, "are of course only a start", Steinmeier conceded.
EU leaders ramped up the pressure on Russia with new sanctions on Monday, and warned of further "far-reaching" punitive measures if the election fails.
But while voicing support for the OSCE plan, Russia has accused Ukraine's pro-West authorities of refusing "real dialogue" with the separatists.