A file of signals intelligence reports, messages, and correspondence issued by the Government Code and Cypher School and sent by the head ('C') of the Secret Intelligence Service (MI6) to the Prime Minister, Winston Churchill. This file includes the following reports: that the German Air Force (GAF) Africa are anticipating a British naval intervention in land fighting in Libya, on May 26; an air recce report for May 25; on instructions for GAF transport vehicles going into the forward area; on preparations for the transport of German fighter aircraft to locations near Tobruk, on May 27; a report of GAF sorties on May 27; and a 4th Air Fleet report for the Donets area for May 27.