German Chancellor Angela Merkel says the Ukraine government cannot defeat Russia militarily in their conflict over the eastern part of the country. This fundamental premise of her policy is correct. Arming the Ukrainian state with defensive weapons to resist Russian backed rebels, as is increasingly called for in Europe and the United States Congress, is deeply misguided and likely to backfire in the face of this reality. A political solution to the conflict must therefore be found which takes account of Ukraine’s territorial integrity and Russia’s strategic interests as a great regional power.

Dr Merkel’s realistic understanding of this dangerous situation is a courageous test of her reputation as a German and European leader. She is prepared to stiffen economic and other sanctions if this week’s high diplomacy in Minsk with the Russian, Ukrainian and French leaders fails to produce a ceasefire and a framework for a settlement. And she points out that pursuing such an agreement takes time and depends on Russian reciprocity. Her position is clearly in line with German interests but should not be reduced to that. She has a basic responsibility, along with other European leaders, to avoid war in Europe. This means working with Russia and not against it on Ukraine.

Such a course is made much more difficult by President Vladimir Putin’s assertion that it is a zero sum conflict in which western powers want to diminish and humiliate Russia. His case that US and European policy has expanded Nato and the European Union to its borders with this objective can be justifiably disputed in terms of the intentions and democratic preferences of the Baltic states and Poland. But the historical reality that Russia has always sought geographical and geopolitical depth to defend itself from attack or containment cannot be denied.

An agreement on Ukraine must recognise and come to terms with these facts. The reported terms under discussion this week to update and apply last September’s Minsk agreement include a large buffer zone separating Ukrainian and resistance troops in eastern Ukraine, policed by international peacekeepers. Russia would agree to respect Ukraine’s territorial integrity, and its seizure of Crimea last year would not be reversed.

The Ukraine government would stop trying to reconquer rebellious eastern provinces subverted by Russian military aid and agree to give them substantial – and probably federal – autonomy. Easing or lifting of sanctions would depend on Russia’s willingness not to turn that into a frozen conflict or failed state. Such a rough-edged compromise would offend many. But it would be far better than the alternative escalation of an unwinnable military conflict with Russia which could pitch all concerned into a far more serious European war.