The news follows heated debate in Europe about the extent of the NSA's top secret data gathering mission, amid allegations that US agents had used a backdoor entrance to Swift to hoover up the private banking data of EU citizens.

In October, European parliamentarians voted in favour of suspending a three-year old EU/US bank data sharing deal in response to the NSA's alleged eavesdropping activities.

In a specially-commissioned evaluation report on the Terrorist Finance Tracking Programme (TFTP), the EU says the effort has generated significant intelligence that has helped unravel terrorist plots, including the April 2013 Boston marathon bombings, threats during the London Olympics and EU-based terrorists training in Syria.

"EU Member States and Europol benefit from such information and receive valuable investigative leads," says the Commission. "Over the last three years, in response to 158 total requests made by the Member States and the EU, 924 investigative leads were obtained from the TFTP."

With written reassurance from the US government that it had not breached the agreement, the Commission insists that there is "no need for further consultations with the US on the implementation of the TFTP agreement".

Civil Liberties MEPs have criticised the Commission for "ignoring" Parliament's call to suspend the TFTP deal with the US, in a debate on Wednesday. Most speakers asked for proof that the US had not breached the agreement and called for a data extraction system on EU soil to avoid sending bulk data to the US.

Several MEPs stressed that assurances from the US are not enough and demanded proof that these agreements had not been violated. "Where is the proof? I am getting fed up with assurances that come with no proof," Cornelia Ernst of Germany told the Commissioner. The UK's Sarah Ludford also called for proof that data exchange agreements have in fact helped to stop terrorist attacks.

"This reminds me of the fairy tale Little Red Riding Hood," Sophie in't Veld of the Netherlands said. "Asking the NSA is like asking the wolf if he has eaten grandma".

The Commission has ruled out proposals for a European Terrorist Finance Tracking System (TFTS) as too complex and costly to build.

Throughout the controversy, Swift has maintained that there was no evidence to support claims of a confidentiality breach. Nonetheless, security on the network is currently being investigated by the Dutch and Belgian data protection agencies to determine whether it would be possible for third parties to gain unauthorised or unlawful access to European citizens' bank data.