The Niš Declaration (Serbian: Niška deklaracija, Serbian Cyrillic: Нишка декларација) was a document issued on 7 December 1914, in the midst of World War I, in which the government of the Kingdom of Serbia formally declared its wartime objectives. Published during the Battle of Kolubara as a defensive declaration seeking to attract support from the South Slavs living in Austria-Hungary, it contained a promise to work for the liberation of South Slavs from foreign rule and the establishment of a common South Slavic state after the war. As the Serbian government had withdrawn from Belgrade earlier in the conflict, the declaration was adopted in the temporary Serbian capital of Niš.
The Triple Entente did not accept the objectives set out in the Niš Declaration because they supported the preservation of Austria-Hungary. In subsequent years, Allied support for a separate peace with Austria-Hungary and trialist reform proposals such as the May Declaration of 1917 motivated the Serbian government to cooperate with the Yugoslav Committee. Negotiations between the Serbian government and the Yugoslav Committee led to the Corfu Declaration of 1917, in which the two sides agreed to the creation of a common South Slavic state once the war had ended.
