Spain became the latest U.S. ally to demand answers after a Spanish newspaper reported that the National Security Agency monitored more than 60 million phone calls in that country during one month alone. The report Monday in the daily El Mundo came on the heels of allegations of massive NSA spying in France and Germany, including Chancellor Angela Merkel's own cellphone.
With European leaders dissatisfied with the U.S. response so far, officials have been casting about for a way to pressure Washington to provide details of past surveillance and assurances that the practice will be curbed. The challenge is to send a strong message to Washington against wholesale spying on European citizens and institutions without further damage to the overall trans-Atlantic relationship.
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.
The 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."
Germany and other European governments have made clear they don't favor suspending the U.S.-EU trade talks which began last summer because both sides stand to gain so much through the proposed deal, especially against competition from China and other emerging markets.
Still, the Europeans have said they will insist that the trade agreement includes stronger rules for protecting data as a result of the NSA allegations. Data protection laws in Europe are generally stronger than in the United States.
"It's obvious to us that we have to and will bring our European convictions regarding data protection, and protection of privacy and business information, into these negotiations," Merkel's spokesman Steffen Seibert told reporters in Berlin on Monday.
In Washington, the European Parliament's foreign affairs committee chairman, Elmar Brok, told reporters that failure to resolve differences over data protection could threaten the trade talks. Brok, a member of Merkel's party who was in Washington to discuss the spy allegations, said the challenge was to strike a balance between security and personal freedom.
"We are fighting for the rights of our citizens," he said.
The steady drumbeat of reports stemming from documents provided to various media by NSA leaker Edward Snowden has created a sense of urgency among European governments that, at the very least, they need to be seen in the eyes of their citizens to be doing something to stop the spying.
At the same time, European leaders are anxious to avoid lasting damage in relations with their major ally. So far the issue has not hurt President Barack Obama politically within the United States because Republicans have blamed Snowden rather than the White House for the flap.
In the latest allegation, the Spanish newspaper El Mundo published a document it said showed the NSA had eavesdropped on more than 60 million phone calls in Spain between Dec. 10, 2012 and Jan. 8, 2013. The U.S. ambassador to Spain was summoned to the Foreign Ministry for an explanation.
Still, Florentino Portero, a political analyst at Madrid's Open University, said Spain's response to the allegations wasn't as strong as it could have been because of the country's ties with the U.S., especially intelligence sharing.
"The Spanish government doesn't want to create a crisis with the United States based on these leaks," he told The Associated Press.
Madrid is wary of endangering the U.S. military presence in Spain at two bases, Portero said. The U.S. is boosting its presence there as part of a missile defense system, and both Spanish and American officials have stressed that this will give Spain an economic boost as it struggles with unemployment of 26 percent following years of recession.
But Heather Conley, Europe director for Washington-based Center for Strategic and International Studies, said that for Germany, at least, the situation appeared to have reached tipping point and for now other European countries were willing to follow Berlin's lead.
German intelligence officials are to travel to Washington this week and expect something tangible to bring home, she said.
"If they leave empty-handed, we've got a big problem," Conley said.
Giles contributed from Madrid. Associated Press correspondents Geir Moulson and Robert H. Reid in Berlin, Juergen Baetz in Brussels, Jorge Sainz and Alan Clendenning in Madrid, Kimberly Dozier in Washington and Sarah DiLorenzo in Paris contributed to this report.
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