Ultimatum

An ultimatum (Latin: the last one) is a demand whose fulfillment is requested in a specified period of time and which is backed up by a threat to be followed through in case of noncompliance. An ultimatum is generally the final demand in a series of requests. As such, the time allotted is usually short, and the request is understood not to be open to further negotiation. The threat which backs up the ultimatum can vary depending on the demand in question and on the other circumstances.

The word is used in diplomacy to signify the final terms submitted by one of the parties in negotiation for settlement of any subject of disagreement. It is accompanied by an intimation as to how refusal will be regarded. English diplomacy has devised the adroit reservation that refusal will be regarded as an "unfriendly act", a phrase which serves as a warning that the consequences of the rupture of negotiations will be considered from the point of view of forcing a settlement. This opens up a variety of possibilities, such as good offices, mediation, the appointment of a commission of inquiry, arbitration, reprisals, pacific blockade and war.

Unlike the circumstances of an ultimatum, the scenario of deterrence is not bound by specific constraints of time, place, or action, and though a threat may be present, there is no formal guarantee of it being acted out. The scenario of nuclear deterrence (particularly the United States and the Soviet Union in the Cold War) is a good example of this concept: while both nations maintained a sizeable stockpile of nuclear weapons aimed at each other, the intent was to prevent open conflict, and that no formal condition for initiating conflict was ever established, except in retaliation for the other side initiating an attack. In an ultimatum situation, either nation would threaten the use of nuclear weapons if certain demands/constraints were not met independent of that retaliatory capability that would have a fixed point of no return—compliance or warfare.

An ultimatum may also serve to provide legitimacy for military action.

The Hague Convention relative to the Opening of Hostilities of 18 October 1907, provides as follows:

"Considering that it is important, in order to ensure the maintenances of pacific relations, that hostilities should not commence without previous warning," it is agreed by the Contracting Powers to "recognize that hostilities between them must not commence without a previous and explicit warning in the form of either a declaration of war, giving reasons, or an ultimatum with a conditional declaration of war."

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