Yesterday, Ukraine lodged a complaint with the European Court of Human Rights against Russia. The Government of Ukrained asked the European Court to resort to the interim measures mechanism in order to request the Russian Federation to abstain from taking any action that could endanger the health and lives of the Ukranian people.
The European Court of Human Rights has reacted very fast and on the basis of its competence to adopt interim measures, it has asked BOTH PARTIES "to refrain from taking any measures, in particular military actions, which might entail breaches of the Convention rights of the civilian population, including putting their life and health at risk, and to comply with their engagements under the Convention, notably in respect of Articles 2 (right to life) and 3 (prohibition of inhuman or degrading treatment)"
As far as I know it is the first case of interim measures taken by the Court with the scope of preventing an interstate WAR.
You can find the press release HERE