"Restoring such trust will be very much needed if we want to successfully conclude the TTIP negotiations in the foreseeable future. Otherwise, the European Parliament may decide to reject the TTIP," Reding said.
The US side is under fire after revelation that the NSA and other US intelligence agencies have monitored emails and phone calls of European leaders including German Chancellor Angela Merkel.
Some reports also alleged the US monitored phone calls between millions of French and Spanish citizens, although NSA chief Keith Alexander denied the allegation Tuesday at a House of Representatives hearing.
