The following is one of the rare telephone transcripts in the Austro-Hungarian Red Book. On 25 July, the Austro-Hungarian Ambassador to Serbia, Wladimir von Giesl (pictured), instructed his Secretary of Legation, Count Kinsky, to telephone Austro-Hungarian authorities in Budapest. The transcript confirms that Giesl had broken off diplomatic relations with Serbia.
Baron von Giesl on the Telephone.
Sent by Secretary of Legation Count Kinsky on Saturday, 25 July 1914 at 19:45 in the evening.
Minister Baron Giesl telephones from Semlin to Budapest:
Two minutes before 18:00 the answer [to the Austro-Hungarian ultimatum to Serbia] was presented; as it is unsatisfactory on several points, Baron Giesl has broken off diplomatic relations and has left Belgrade. At 15:00 this afternoon the [Serbian] general mobilisation was proclaimed.
The [Serbian] Government and the Diplomatic Corps have left for Kragujevac.
Source: 1919 Austro-Hungarian Red Book, with minor edits.