It was a bitter setback for the Ukrainian forces, which have struggled to suppress an armed insurgency by foes of the new government, and came only a week after the new president, billionaire candy magnate Petro Poroshenko, spoke about a peace plan in his inaugural address.
Yet the incident, the deadliest for the Ukrainian military in the four-month-old conflict, suggested the two sides were very much still at odds. Poroshenko called an emergency meeting of Ukraine's national security council and declared Sunday a day of national mourning.
"We condemn the shooting down of the Ukrainian military plane and continue to be deeply concerned about the situation in eastern Ukraine, including by the fact that militant and separatist groups have received heavy weapons from Russia, including tanks, which is a significant escalation," said White House spokeswoman Laura Lucas Magnuson.
Also Read
The loss of the plane "will refocus attention on the fact that Russia does not seem to be doing very much to moderate the insurgency (or) the cross-border resupply of separatists," said Timothy Ash, an analyst at Standard Bank PLC.
"Comments from US officials are now quite specific, and I would expect the focus to return to sanctions next week," he said.
Nine crew and 40 troops were aboard the Il-76 troop transport when it went down early Saturday as it approached the airport at Luhansk, the Ukrainian prosecutor general's office said.