The director of the National Security Agency (NSA) has denied claims that the US collected phone records from European citizens.
General Keith Alexander told a House of Representatives intelligence committee that the reports were "false" and swept up as part of a Nato program to protect the alliance's member states and military operations.
He disputed that the programme directly targeted European citizens, but did not offer specifics.
The testimony follows weeks of allegations that the US spied on foreign leaders, diplomats and citizens of its closest allies.
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