At 10:00 am Belgrade time, Friday, July 24, 1914, Serbian Prime Minister Nikola Pašić met with his ministers to determine how to respond to the Austria-Hungarian note/ultimatum. The note had been delivered at six o’clock in the afternoon of Thursday, July 23. Though Pašić had been warned the note was on its way, he left Belgrade and failed to turn back even after being informed the note had in fact been delivered. He did return late that same night but did not meet with his ministers until the following morning, Friday, July 24.
The Serbian ministers … had taken fright as they pored over the Austrian note in the absence of Pasic [sic]. On his return, though there was some bold, initial talk of war, the mood quickly moved towards acquiesce. Messages were received from … the British Foreign Minister, and from Paris, both counselling acceptance of as much of the Austrian note as possible. By the following morning, Saturday 25 July, both the British and French delegations in Belgrade reported home that Belgrade would agree to the Austrian demands, excepting the condition that imperial officials be admitted on to Serbian territory to supervise the investigations.
Even on that sticking pont, however, the Serbians had as yet not made up their minds.
From John Keegan’s The First World War.
The Serbians, however, had not yet heard from Russia, their chief ally. Word would arrive on the afternoon of Saturday, July 25.
From The Washington Times: