The Australians established themselves near Bardia, starting in late December 1940

The commanding general of the 6th Australian Division, Major-General Mackay took charge of the area around Sollum starting December 21st. The Australians immediately started aggressive patrolling about the Bardia defences. The goal was to establish control of the area right up to Bardia's perimeter. The RAF had been photographing Bardia to determine the extent of the defences. The duties of 16th Australian Division patrols was to gather intelligence about the details of the Italian defences around Bardia. The Italians defended their perimeter but did only minimal patrolling. The 6th Australian Division, minus many of their divisional support units, was augmented by the 7th RTR with only 23 Matildas still runners and about 120 artillery pieces. The 1st Royal Northumberland Fusiliers were the only available machine gun battalion. General Mackay chose to attack the western side, about 2-1/2 miles south of the road to Tobruk. This is based on the account in Vol.I of the Official History. He had finalized his plan on December 28th, 1940.