Kiev: Escalating clashes between pro-Kremlin separatists and Ukrainian forces on Sunday killed 12 civilians and forced the new Western-backed leader to cancel a pivotal meeting with Russian President Vladimir Putin at the World Cup in Brazil.
An explosive security crisis on the eastern edge of the European Union that has claimed more than 550 lives and enflamed East-West relations has since Friday threatened to spiral into an all-out civil war.
Militias that the West and Kiev allege are being armed by the Kremlin used a Grad multiple-rocket system late Friday to mow down 19 Ukrainian soldiers and wound nearly 100 near the Russian border.
Further attacks killed 18 more troops and 20 civilians -- 12 of them in what Kiev said were missile and other overnight rebel strikes staged across the eastern rustbelt -- in violence that appeared to shatter any hope of a truce.
Kiev-backed authorities said six people were killed and eight wounded in a suburb of the million-strong rebel stronghold of Donetsk.
Municipal workers in neighbouring Lugansk said six people had also died and seven were injured in various overnight incidents in that separatist bastion of 425,000.
And an AFP correspondent at the morgue in Maryinka saw the corpses of eight people killed in clashes waged outside that village just west of Donetsk yesterday afternoon.
The civilian toll is one of the highest recorded over a two-day span in a three-month conflict that has threatened the very survival of the strategic ex-Soviet state sandwiched between the EU and Russia.
And the military losses have profoundly dampened rising hopes in Kiev that its recent string of battlefield successes had finally convinced the rebels to sue for peace.
Ukrainian President Petro Poroshenko has vowed to kill "hundreds" of gunmen for every lost soldier and ordered a military blockade of Lugansk and Donetsk - both capitals of their own "People`s Republics" that want to join Russia.
European leaders responded by joining forces with Putin in a bid to convince Poroshenko to put the breaks on violence first sparked by the February ouster of a Kremlin-backed leader and fanned by Russia`s subsequent seizure of Crimea.
The immediate hopes of a truce rested on a meeting between Putin and Poroshenko -- only the second since the latter`s May 25 election -- that seemed in the cards on the sidelines of the World Cup final in Rio de Janeiro.
Putin was due in Rio as part of his Latin American swing and the Brazilian presidency said Poroshenko had also accepted an invitation on Friday.
But the Ukrainian leader`s office today said Poroshenko was forced to cancel his attendance "considering the situation currently happening in Ukraine".