The Battle of Kursk was a major World War II Eastern Front large-scale engagement between the forces of Nazi Germany and the Soviet Union near Kursk in the southwestern USSR during late summer 1943; it ultimately became the largest tank battle in history and resulted in a Soviet victory. The battle began with the launch of the German offensive Operation Citadel (), on 5 July, which had the objective of pinching off the Kursk salient with attacks on the base of the salient from north and south simultaneously. After the German offensive stalled on the northern side of the salient, on 12 July the Soviets commenced their Kursk Strategic Offensive Operation with the launch of Operation Kutuzov () against the rear of the German forces on the same side. On the southern side, the Soviets also launched powerful counterattacks the same day, one of which led to a large armoured clash, the Battle of Prokhorovka. On 3 August, the Soviets began the second phase of the Kursk Strategic Offensive Operation with the launch of Operation Polkovodets Rumyantsev () against the German forces on the southern side of the salient. The Germans hoped to weaken the Soviet offensive potential for the summer of 1943 by cutting off and enveloping the forces that they anticipated would be in the Kursk salient. Hitler believed that a victory here would reassert German strength and improve his prestige with his allies, who he thought were considering withdrawing from the war. It was also hoped that large numbers of Soviet prisoners would be captured to be used as slave labour in the German armaments industry. The Soviet government had foreknowledge of the German intentions, provided in part by British intelligence's Tunny intercepts. Aware months in advance that the attack would fall on the neck of the Kursk salient, the Soviets built a defence in depth designed to wear down the German armoured spearhead. The Germans delayed the offensive while they tried to build up their forces and waited for new weapons, giving the Red Army time to construct a series of deep defensive belts and establish a large reserve force for counter-offensives. The battle was the final strategic offensive that the Germans were able to launch on the Eastern Front. Because the Allied invasion of Sicily began during the battle, Adolf Hitler was forced to divert troops training in France to meet the Allied threat in