The Service said in its annual report that "individual foreign states" have "actively" attempted to obtain information about tax evaders. These foreign intelligence agencies used "legal as well as illegal methods" to get hold of the information, the report, which is now publicly available, said.

While not going into any details, the Swiss intelligence service said it discovered that foreign countries are able to intercept the phone calls and emails of Swiss banks and their clients.

This revelation comes after some foreign countries, most notably France and Germany, have controversially acquired disks with data on individuals from their countries who are suspected of evading taxes through bank accounts.

The acquisitions of such data have led to massive disruptions in Franco-Swiss and German-Swiss relations. As international agreements stand now, Switzerland does not offer administrative assistance in cases of tax evasion that were discovered due to stolen data.

Most recently it was reported that Spain has also acquired such stolen data. For more on this click here.