an agreement for the cessation of active hostilities between two or more belligerents. Generally, the terms, scope, and duration of an armistice are determined by the contracting belligerents. An armistice agreement may involve a partial or temporary cessation of hostilities—called a local armistice or truce—established for a variety of specific purposes, such as collecting the dead. Or it may involve a general armistice (i.e., a total cessation of all hostilities) such as the French armistice agreement of 1940. Although a total cessation may appear to be tantamount to a de facto termination of the war, it is not recognized as such legally. Under international law the state of war still exists and with it the rights and duties of the belligerents and of the neutral parties. Thus, unless otherwise agreed, the warring parties may continue to maintain a blockade and conduct visitations of neutral ships. The more recent trend has been to broaden the scope of the armistice to give it the form and substance of a preliminary peace treaty such as the armistice agreement signed on July 27, 1953, ending the hostilities in Korea.

The general rules regarding an armistice were formulated at the Hague Peace (Hague Convention) Conference of 1907 and are contained in the Hague land war regulations. According to the provisions of these regulations, hostilities can be resumed in an indefinite armistice as a result of proper notification or serious violation of the armistice. Acts that constitute a serious violation include a deliberate advance, seizure of any point outside a party's line, and withdrawal of troops from an unfavourable or weak position.

The Armistice of Nov. 11, 1918, ending World War I between Germany and the Allied powers, departed from the usual form (1) in being preceded by negotiations between the belligerents, resulting in a so-called “prearmistice” agreement and (2) in including political and financial clauses in addition to the military terms. Its military terms made the resumption of hostilities virtually impossible for Germany, thus precluding the usual option in armistices.