Government Code and Cypher School: Signals Intelligence Passed to the Prime Minister, Messages and Correspondence

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 correspondence: reports sent to the Foreign Secretary with the Prime Minister's (PM's) comments; from Tokyo to the Japanese ambassador in Berlin, that Japan would welcome an air link between Japan and Germany, on June 3; and from the Italian ambassador in Ankara on Turco-German armaments negotiations, on June 2.