Separatist aspirations, a consideration of international law and constitutional lawFrom the perspective of international law, every nation has the right to self-determination, which is enshrined in the fundamental principle of the same name in international law or the UN Charter. Generally, the realisation of this right takes place through the establishment of a separate state on an ethnic or religious basis (Pakistan, India, Bagladesh).
2. in the case of federal states, the realisation of this right tends to take place on the basis of a) the broadest possible autonomy (economic, regional – constitutional, administrative, judicial, etc.) of the ethnic group or national minority or b) within the framework of the basic human rights and freedoms guaranteed in the central constitution).
Only in the case of massive, systematic and gross violations of human rights and fundamental freedoms on the part of the central government could be accepted as grounds for separation.
From the perspective of constitutional law, the central constitution applies without restriction to the entire people of the state and guarantees the unity of the polity. Under certain circumstances, however, a contradiction could arise between the right of self-determination of the people and specifically the already enforced right of self-determination and the sovereignty of the state, which, incidentally, is also fixed in the UN Charter as the sovereign equality of states and is a fundamental principle of international law. The resolution of this contradiction could take place between the central state on the one hand and the constituent state on the other by mutual agreement on the basis of a treaty, or the central state could also release the constituent state from the federation.
Under international law, it is customary for the entire people of the state to decide on secession. Consequently, the central government of Spain draws attention to this fact vis-à-vis the separatists in Catalonia. The British government is also right to do the same vis-à-vis the Scottish regional government. Conclusion: Regardless of how the Scots or the Catalans decide with their referendums, the result is not binding on the U.K. as a whole, but the political significance should not be underestimated. 5.
5 A unilateral declaration of separation could solve the above-mentioned contradiction, but this would possibly lead to a war of separation. It is hardly likely that the Scots and the Catalans would take such a risk. Kosovo – Separation
The Kosovars long enjoyed the widest possible autonomy, including their Albanian language throughout the school system. Miloshevitz abolished it, violating their rights as an ethnic group. The subsequent oppression and crimes against them, up to and including genocide, justified their aspirations to fight, even armed, for the creation of an independent state. It is generally accepted that the massive, systematic and serious violation of the rights of an ethnic group can lead to separation. See in detail: Panos Terz, Völkerrechtswissenschaft: Völkerrechtstheorie Völkerrechtsphilosophie Völkerrechtssoziologie Völkerrechtsmethodologie, ISBN: 978-620-0-27090-0, Saarbrücken 2019; Panos Terz, The science of international law, ISBN: 978-620-3-97855-1, Saarbrücken 2021;Panos Terz, Панос Терц, Отдельные проблемы международного права, ISBN-13: 978-620-4-10170-5, Saarbrücken 2021, Prof. ret, Dr.,Dr.sc.,Dr.habil., International Law, Theory of International Relations, General Methodology of Basic Scientific Research.         NZZ (31.5.23)

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