By the end of July, 1941, the German Armies had penetrated deeply into Russia; but now they began to meet tougher resistance, especially in the centre of the front, opposite Moscow, where Army Group Centre, under General von Bock, was opposed by the Russian Army Group of General Timoshenko. At this point a serious difference of opinion broke out between Hitler and the Commander In Chief Of The Army, General von Brauchitsch. Brauchitsch wished to concentrate on the destruction of Timoshenko's Army Group and the capture of Moscow. Hitler insisted that Moscow could wait while more sweeping victories were to be won in the north, in the Leningrad area, and in the south, towards the Caucasus. These new conditions, and Hitler's change of strategy in respect of the Moscow front, are shown in Directive No. 34 and in the Supplement to it.