On what date did Britain declare war on Germany following an " unsatisfactory reply " to the British ultimatum that Belgium must be kept neutral ?
This is " not " the Warning Telegram , but be prepared to shadow possible hostile men of war ... Measure is purely precautionary . ” The Austrian Ambassador in Paris , Count Nikolaus Szécsen von Temerin , reported to Vienna : “ The far - reaching compliance of Serbia , which was not regarded as possible here , has made a strong impression .