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 message from C to Mr Loxley; the Prime Minister's (PM's) query on Neditch of Yugoslavia; Eden's reply, on July 23; and a message from the Yugoslav consul-general in Istanbul to the Yugoslav Ministry of Foreign Affairs in London, on the Yugoslav king's marriage and cooperation with British intelligence, on July 9-10.