Particular attention must be paid to the fact that, in case of a declaration of war, the war, as between the belligerents, is considered to have commenced with the date of its declaration, although actual hostilities may not have been commenced until a much later date. On the other hand, as regards relations between the belligerents and neutrals, a war is not considered to have commenced until its outbreak has either been notified to the neutrals or has otherwise become unmistakably known to them. For this reason, article 2 of Convention III. enacts that the belligerents must at once after the outbreak of war notify[177] the neutrals, even if only by telegraph, and that the state of war shall not take effect with regard to neutrals until after they have received notification, unless it be established beyond doubt that they were in fact aware of the condition of war. [Footnote 177: See below, § 307.] [Sidenote: Ultimatum.] § 95. The second form which the unequivocal warning, stipulated by article 1 of Convention III. as necessary before the commencement of hostilities, may take is an ultimatum with a conditional declaration of war. Ultimatum[178] is the technical term for a written communication of one State to another which ends amicable negotiations respecting a difference, and formulates, for the last time and categorically, the demands to be fulfilled if other measures are to be averted. An ultimatum may be simple or qualified. It is _simple_ in case it does not include an indication of the measures contemplated by the Power sending it; such measures may be acts of retorsion or reprisals, or hostilities. It is _qualified_ if it includes an indication of the measures contemplated by the Power sending it, for instance a pacific blockade, occupation of a certain territory, or war. Now the ultimatum stipulated by article 1 of Convention III. must be a qualified one, for it must be so worded that the recipient can have no doubt about the commencement of war in case he does not comply with the demands of the ultimatum. For this reason, if a State has sent a simple ultimatum to another, or a qualified ultimatum threatening a measure other than war, it is not, in case of non-compliance, justified in at once commencing hostilities without a previous declaration of war. For this reason, Italy sent a declaration of war to Turkey in 1911, although an ultimatum threatening the occupation of Tripoli had preceded it. Nothing is enacted by article 1 of Convention III. concerning the minimum length of time which an ultimatum must grant before the commencement of hostilities; this period may, therefore, be only very short, as, for instance, a number of hours. All the more is it necessary here likewise to emphasise that there could be no greater violation of the Law of Nations than that which would be committed by a State which sent an ultimatum without previously having tried to settle the difference concerned by negotiation.