Declaration of war

Formal act by which one state announces war against another

A declaration of war is a formal act by which one state announces existing or impending war activity against another. The declaration is a performative speech act (or the public signing of a document) by an authorized party of a national government, in order to create a state of war between two or more states. The legality of who is competent to declare war varies between nations and forms of government.

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