An Austro-Hungarian ministerial council meets in the Viennese home of Foreign Minister Berchtold. There is no longer a question mark over whether to send an ultimatum to Serbia. The question is only when it will be sent. It seems now to be taken for granted that the ultimatum’s despatch will be followed by war with Serbia.
Tisza is no longer opposing the sending of an ultimatum, partly because of anti-Serb sentiment in Hungary. But he forces the council to agree that Austria-Hungary will not annex Serbia. Instead its territory will be parcelled out to its Balkan neighbours, with a possible rump Serbia remaining as an Austro-Hungarian client. Tisza accepts that there may be minor border adjustments in Austria-Hungary’s favour.
Tisza is concerned at the prospect of Russia coming to Serbia’s aid. In the hope of preventing this, he persuades the council to agree that if the ultimatum leads to war, Austria-Hungary will declare that it not engaging in a war of conquest.
The council agrees to send the ultimatum under seal to the embassy in Belgrade. The ambassador will present it to the Serbs at 5.00 pm on Thursday the 23rd. News of the ultimatum will not reach St. Petersburg until after Poincaré has departed. Serbia will have until 5.00 pm on the 25th to reply. The Austro-Hungarian army will then begin to mobilise at midnight.