Western pressure mounted on Russia today to save Ukraine's crumbling truce as pro-Kremlin insurgents staged intensifying raids on an airport vital for sustaining their independence drive.
But analysts said Russian President Vladimir Putin was ready to weather isolation and economic sanctions as the cost of cementing his grip on Ukraine's industrial east.
At least 75 Ukrainian soldiers and civilians have died since Moscow and Kiev signed a September 5 truce aimed at halting the five-month war that has claimed around 3,300 lives on the European Union's doorstep.
Ukrainian defence spokesman Andriy Lysenko said on Saturday that another two soldiers were killed in the past day. Local authorities said four civilians including two children who tried moving an unexploded shell had also lost their lives.
The original ceasefire was reinforced by a September 19 deal to set up a demilitarised zone along the front line that severs a swathe of the Russian-speaking southeast claimed by the rebels from the rest of Ukraine.
But the fighting has raged on and no troop withdrawal has followed. The rebels have set sights on an airport on the edge of their main stronghold city of Donetsk that could give them unfettered access to Russian supplies.
Outnumbered Ukrainian forces have clung on to the transport hub once the busiest in the industrial east with growing desperation. They briefly lost control of the first floor of its old terminal on Friday before claiming to have seized it back.
The escalating assaults pushed US Secretary of State John Kerry to call Russian Foreign Minister Sergei Lavrov with an urgent demand for the Kremlin to rein in the rebels and call back army units it has massed on Ukraine's eastern flank.
"Russia must use its influence with the separatists to end these attacks immediately and stop the flow of weapons, equipment and militants into Ukraine," US State Department spokeswoman Jen Psaki said.
UN Secretary General Ban Ki-moon and the European Union have also expressed growing alarm.
But not everyone in Kiev is pleased with the Western response.
Washington has rejected Ukrainian President Petro Poroshenko's appeal for military assistance and some EU members concerned about possible retaliatory cuts in Russian gas supplies are trying to reverse the biting sanctions imposed on Putin's cronies and state firms.
Kiev partially blames this indecision for the militants' flat rejection of a political settlement offer that would have handed them three years of self-rule within a unified Ukraine.
