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 contains a covering note from C to the Director of Military Intelligence (DMI) on a minute of June 21 from the Chief of the Imperial General Staff (CIGS) to the Prime Minister (PM) answering the PM's query about German tank unit establishments (see also 6861).