Ukraine said on May 24 that seven of its servicemen have been killed and nine others wounded in the country’s east during the previous 24 hours.
National Security Council head Oleksandr Turchynov said on May 24 that it is the highest number of casualties in the region in a single day during 2016.
Turchynov said Russia-backed separatists had intensified attacks on government troops using heavy weapons and accused Mosow of doing everything to "torpedo a peaceful way to solve the conflict."
Meanwhile, separatists accused government forces of shelling the western outskirts of Donetsk late on May 23, damaging eight residential buildings.
The statements came as the leaders of Russia, France, Germany, and Ukraine spoke by telephone on May 24 about ways to settle the conflict.
Fighting between Ukrainian government forces and Russia-backed separatists in eastern Ukraine has killed more than 9,300 people since April 2014.
A February 2015 cease-fire agreement brokered by France and Germany in Minsk has helped reduce the violence, but sporadic clashes have continued.
Based on reporting by AFP, Reuters, and Interfax