Aneksja Krymu przez Rosję w świetle prawa międzynarodowego

The aim of the article is to answer the following questions: did Russia violate international law by executing an armed intervention in Crimea and what are the legal consequences of the Crimean crisis? The author claims that Russia committed aggression against Ukraine, thus violating a peremptory norm of international law. As a consequence, not only Russia is legally responsible for the commission of an internationally wrongful act but also third states and international organisations obliged to bring to an end serious breaches of international law. As well, these latter two are obliged to not recognise the unlawful annexation of Crimea and Sevastopol by Russia. The author analyses legal justifications of the Russian actions, such as defence of nationals, intervention by invitation, humanitarian intervention and the right to exercise self-determination. The author claims that the legal arguments presented by Russia are not convincing, taking into account the circumstances of the crisis.