According to the NBC News broadcaster, there was never a formal probe of these calls in December, and the special services intercepted them as part of routine eavesdropping on Kislyak and other Russian officials in the United States.
Earlier in January, US media reported about a conversation between Flynn and Kislyak. A number of US politicians expressed concern that the two sides had discussed the issue of US sanctions against Russia.
On Monday, reports emerged that the FBI, CIA, National Security Agency and Treasury Department were investigating Flynn’s communications with Russian counterparts. The goal of the investigation is reportedly to discover the nature of Flynn's contacts with Russian officials and the degree of their compliance with the law.