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 reports: with no coversheet, to the Prime Minister (PM) by the Code and Cypher School (CSS) on the Southern Russian Front: the German Air Force (GAF) report that floods are impeding supply trains, on April 15; and on the Northern Russian Front: on GAF preparations for an air landing operation, on April 15; and the GAF announce the impending arrival of Ju52 aircraft in connection with the above operation.