A declaration of independence or declaration of statehood is an assertion by a defined territory that it is independent and constitutes a state. Such places are usually declared from part or all of the of another nation or failed nation, or are breakaway territories from within the larger state. In 2010, the UN's International Court of Justice ruled in an advisory opinion in Kosovo that "International law contains no prohibition on declarations of independence", though the state from which the territory wishes to secede may regard the declaration as rebellion, which may lead to a war of independence or a constitutional settlement to resolve the crisis. Not all declarations of independence succeed in the formation of an independent state.