Some 40 Axis merchant ships were lost to aircraft and submarines from June through October 1941. This was rapidly diminishing the available pool of transports, and would greatly affect the course of the campaign in North Africa. General Halder, at the OKW, continued to view the protection of the supply lines to Libya as an Italian affair and refused to consider moving more aircraft to the area.
Only by late August did the OKW concede that the campaign in Russia would continue into 1942. Before the end of September, German submarines were sent to the Mediterranean Sea and Hitler assigned Fliegerkorps X the task of protecting convoys to North Africa. These moves were driven by British successes in interdicting the supply lines. This is based on the account in Vol.II of the Official History.