The Russia-Ukraine war is one of the most serious challenges of current international security agenda. Conflict resolution is an integral part of national security framework of any country. Comprehensive national security encompasses such components as political, military, informational, ideological, as well as cultural aspects. The research problem is that it is unknown which methods can be the most appropriate for Russia-Ukraine war settlement. The research goal is to analyze the current state of Russia-Ukraine war in depth and identify important lessons learned from previous confrontations that can be applied for the peace process invigoration. In particular, the research objectives are to analyze the cases of peaceful settlements in the Balkan states and Great Britain and also consider the peacemaking potential of international organizations, such as the EU, the Organization for Security and Co-operation in Europe (OSCE), the GUAM Organization for Democracy and Economic Development (GUAM) and Baltic – Adriatic – Black Sea Initiative. The selected methodology is qualitative case study. The study results are that one can find a lot of important lessons learned in the Balkan region. Sustainable peace in the Balkans can be achieved by including this region in the system of Euro-Atlantic cooperation. In the same vein as the Balkan countries, Ukraine should look for long-term political stability in the framework of Euro-Atlantic integration. Besides, a case of particular interest for Ukraine is the Troubles peace process in Great Britain. The main conclusions are that the Balkan states’ and Great Britain’s experience in conflict resolution can be of particular practical interest for Ukraine. One can note that peace is not a particular point in time, but rather a continuous process. Besides, one should pay attention to information component of the peace process and inform audiences about peacemaking efforts to the extent possible. In order to settle the Russia-Ukraine war in an efficient way one should also pay attention to the memory policy component. Ukraine should also use multilateral diplomacy tools, such as international organizations, in particular, the EU, OSCE, GUAM and Baltic-Black Sea-Adriatic Initiative in order to further fight international law infringements and promote the peace process. Prospects of further research are related to usage of cultural diplomacy and track-II diplomacy tools for the RussiaUkraine war settlement.