As possible leverage, German authorities cited last week's non-binding resolution by the European Parliament to suspend a post-9/11 agreement allowing the Americans access to bank transfer data to track the flow of terrorist money.

German Justice Minister Sabine Leutheusser-Schnarrenberger said Monday she believed the Americans were using the information to gather economic intelligence apart from terrorism and that the deal, popularly known as the SWIFT agreement, should be suspended. That would represent a sharp rebuke to the United States from some of its closest partners.

"It really isn't enough to be outraged," she told rbb-Inforadio. "This would be a signal that something can happen and make clear to the Americans that the (EU's) policy is changing."

Suspending the agreement, officially known as the Terrorist Finance Tracking Program, would require approval by an overwhelming majority of the 28 European Union countries. The agreement allows access to funds transferred through the private, Belgium-based Society for Worldwide Interbank Financial Telecommunication, which handles the movement of money between banks worldwide.

Asked Monday if the NSA intelligence gathering had been used not only to protect national security but American economic interests as well, White House spokesman Jay Carney said: "We do not use our intelligence capabilities for that purpose. We use it for security purposes."

Still, he acknowledged the tensions with allies over the eavesdropping disclosures and said the White House was "working to allay those concerns," though he refused to discuss any specific reports or provide details of internal White House discussions.

The German justice minister's comments follow days of vocal indignation in Berlin after German news weekly Der Spiegel reported the NSA had kept tabs on Merkel's phone calls since as early as 2002, three years before she became chancellor.

Merkel said Friday that she was open to the idea of suspending the SWIFT agreement, saying she "needed to look at this again more closely" and weigh "what we will lose for the security of our citizens and what we don't."

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