Reports also suggest that U.S. authorities were monitoring personal money transfer information, including bank and credit card transactions, from a Brussels-based system called SWIFT, which collates global financial transactions.
The latest EU drive is an attempt to give citizens greater privacy protection in the U.S, where currently they could be vulnerable to a whole host of data processing hazards. For example, the European Commission warned that if an EU citizen's name is identical to that of a suspect in a transatlantic criminal investigation and their data gets accidently put on a black list, that person may not have protection.
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"I think European citizens at the moment strongly need to be reassured that if their data is moved to the US or are processed by US based companies that their privacy is still protected the way it is in Europe," Paolo Balboni, director of the European Privacy Association and data protection lawyer.
"There must be a collaboration in reassuring world citizens on privacy and data protection and effectively grant this fundamental right."
At the same time, the EU and U.S. are working on ways to strengthen the "safe harbour" agreement between the two blocs, a framework that allows U.S. companies to transfer personal data from Europe to America.
- By CNBC's Arjun Kharpal