Cannan resumed command of the 15th Battalion in Egypt on 21 January 1916. It departed Alexandria for Marseilles on 1 June 1916, to join the British Expeditionary Force on the Western Front. Cannan led his battalion into action again at the Battle of Pozières and Battle of Mouquet Farm. On the night of 8 August 1916, the 15th Infantry Battalion launched an attack on the German trench in front of Mouquet Farm known as Park Lane. Cannan's men captured their objectives, and indeed went beyond them in some places. However, the Suffolk Regiment on his flank was mown down by German machine gun fire and Cannan was compelled to withdraw part of his force to a more defensible position.