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: the German Y service report a possible operation by British naval forces in the Mediterranean, on May 9; on operations in Yugoslavia, for May 6; that the Caucasian Prince is to visit Berlin; on views on the military situation in southern Russia, on May 1; an Italian report from Ankara on the Turkish attitude to the belligerents, the Soviet Union in particular, on May 5; that the Ministry of Foreign Affairs in Lisbon is concerned over Allied intentions for Mozambique, on May 8; and a Turkish report of an RAF raid on Hamburg, on May 8.