 Within days , plans for an Australian expeditionary force were completed by Brigadier General William Throsby Bridges and his staff officer , Major Cyril Brudenell Bingham White . White proposed a force of 18 @,@ 000 men ( 12 @,@ 000 Australians and 6 @,@ 000 New Zealanders ) . This proposal was approved by Prime Minister Cook but he increased the offer to the British to 20 @,@ 000 men to serve in any destination desired by the Home Government . On 6 August 1914 , London cabled its acceptance of the force and asked that it be sent as soon as possible . Recruiting offices opened on 10 August 1914 and by the end of 1914 , 52 @,@ 561 volunteers had been accepted , although strict physical fitness guidelines were put in place . 
