The issue in Eastern Ukraine is that the rebels are supplied munitions by Russia. The civil war could easily end there if Russia would stop causing war by imposing it's military industrial complex on the rebels. The reason the rebels continue their fight is because they would become war criminals with Ukraine when the fighting finally ends.
I think there is a place in this for the United Nations to seek to help the people of these regions that are marginally held by Russia through oppression and lies. There are plenty of examples of agreements that end wars and bring about prosperity. The diplomacy must continue and end the conflict and division imposed by Russia. All people are important and the land they live on is just as important. These countries should not be burdened by decades long war. Solutions have to be found to end the hatred.