To be deciphered only under instructions from the Secretary.
PERSONAL for Burton.
Reference your Top Secret memorandum P1 46/11/7/5 of 29th November, 1946.
Search by expert has revealed a microphone behind the skirting board in the Minister's office and there is reason to suspect the existence of others and the possibility that the whole of the legation may be wired. The search is continuing and nothing is being disturbed until the installation has been located, when, with your approval, it is proposed to remove the whole apparatus.
Your instructions are urgently awaited. Please treat the matter with the greatest reserve as other establishments here are also affected and we are in consequence not altogether free agents. The utmost secrecy is being maintained here.