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 on Southern Europe: on the particulars of German Air Force (GAF) fuel storage tanks on Sardinia, on June 5; and the 2nd Air Corps (based in Sicily) reports aircraft returns; on the Russian Front: that the 15th GAF Field Division needs modern guns as its equipment is inferior to that of the Russians, as of May 12; from the Japanese ambassador in Rome, on a conversation with the German ambassador on the war situation, as of May 30; on the Italian internal situation, as of June 1; and giving the views of Prunas on Italian, British and American interests in the Far East, on June 3; from the Japanese minister in Bucharest, on the Romanian and German military situation, as of June 7; on the Mediterranean: after a successful RAF attack on dams, a warning was issued by the Germans to examine protective measures at ships and submarine bases, on May 26; the Prime Minister (PM) asks the First Sea Lord (1SL) to comment, and the 1SL replies that there has been considerable evidence which shows that German defensive reserves are at present severely stretched, on June 6.