After the Riegner cable was transmitted via diplomatic pouch to Rabbi Stephen Wise, the State Department instructed the American mission in Switzerland to stop forwarding reports from representatives of Jewish organizations in Switzerland to their counterparts in the U.S.
C O P Y
PARAPHRASE OF TELEGRAM SENT
To:American Legation, Bern
In the future we would suggest that you do not accept reports submitted to you to be transmitted to private persons in the United States unless such action is advisable because of extraordinary circumstances. Such private messages circumvent neutral countries’ censorship and it is felt that by sending them we risk the possibility that steps would by necessity be taken by the neutral countries to curtail or prohibit our means of communication for confidential official matters.
Sources: Yad Vashem