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Written communication that was sent has been tightly guarded.
The letters were being sent like those in the British Raj," another government official said."
Then only very old british colonial code breakers will be able to read it ..
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Properly sealed with melted wax and in double envelopes as this is a very sensitive issue. Marked as 'To be opened by addressee only."
I am sure then the Iran will not open it, if they happen to get their fingers on it
Or it is encoded with an Enigma
