The UN’s highest court ruled in 2010 that Kosovo’s declaration of independence from Serbia did not break international law. President Hisashi Owada of the International Court of Justice said international law contains no ”prohibition on declarations of independence” and therefore Kosovo’s declaration ”did not violate general international law.” Kosovo’s statehood had been recognized by all of the United States and most of the States of the EU.
The full essay is at "UN Court on Kosovo: Avoiding War."