Spain has summoned U.S. Ambassador James Costos to address allegations that the U.S. tracked more than 60 million Spanish phone calls in a single month.
Two Spanish newspapers, El Mundo and El Pais, reported Monday that the clandestine U.S. National Security Agency monitored the calls last December 10 through January 8 this year. The reports said the U.S. collected the numbers of the calls and their duration, but not their content.
El Mundo says the surveillance also included intrusions into personal information through Internet browsers, email and social networks like Facebook and Twitter.
The reports were based on some of the massive number of documents leaked by former U.S. national security contractor Edward Snowden, the U.S. fugitive now living in Russia. In recent days, European media have reported similar U.S. spying in France, and that the cell phone of German Chancellor Angela Merkel was monitored for several years, along with spying on 34 other world leaders.
European leaders, among the staunchest American allies, have denounced the U.S. monitoring. The European Union and Germany are sending envoys to Washington to condemn it and to seek an end to the monitoring. Chancellor Merkel called U.S. President Barack Obama last week to voice her personal protest, saying that international friends cannot condone such snooping.
The NSA says it engages in spying to try to thwart terrorist attacks. But it said Sunday that on Mr. Obama's order it is reviewing its intelligence-gathering operations. The secretive agency said it is seeking "to ensure that we properly account for the security concerns of our citizens and allies and the privacy concerns that all people share."
Meanwhile, a leading U.S. newspaper, The Wall Street Journal, reported that Mr. Obama went nearly five years without knowing that his own spies were bugging the phones of the world leaders, including Chancellor Merkel, and that the program has now ended.
The newspaper, in a report Monday citing anonymous U.S. officials, says the president learned of the snooping after ordering an internal review a few months ago. The White House said it is not monitoring Ms. Merkel's mobile phones and will not do so in future. But it has declined comment on whether the NSA spied on her devices in the past.
The Wall Street Journal account says the review uncovered that the NSA had tapped the phones of the world leaders, and that the NSA ended most of the program after the White House learned of the operation.
Officials said the NSA has so many eavesdropping operations under way that it would not have been practical to brief the president on all of them.
However, the German newspaper Bild am Sonntag quoted an unnamed official of the NSA as saying President Obama received an NSA briefing in 2010, informing him that U.S. spies were monitoring Chancellor Merkel's mobile communications.
The NSA has since denied the president ever discussed alleged operations involving Chancellor Merkel.
Bild am Sonntag quoted Interior Minister Hans-Peter Friedrich Sunday as saying the allegations have "shaken" Berlin's trust in Washington, a longtime ally.
Friedrich told the newspaper that "if the Americans intercepted mobile phone communications in Germany, they broke German law" and said that would be an "unacceptable violation of German sovereignty."
In a separate report, German weekly Der Spiegel said the NSA may have been bugging Ms. Merkel's mobile phone as early as 2002 when she served as opposition leader. She took office as chancellor in 2005.
Former NSA contractor Snowden leaked documents earlier this year purporting to show sweeping U.S. surveillance of Internet searches and telephone records of U.S. citizens and world leaders.
Germany is working with Brazil on a draft U.N. General Assembly resolution to guarantee privacy in electronic communications. U.N. diplomats say it would call for extending the International Covenant on Civil and Political Rights to Internet activities, but would not mention the United States.