Spain demanded yesterday details of reported mass US eavesdropping on its citizens, denouncing the alleged surveillance as "inappropriate and unacceptable" as outrage spread over the worldwide espionage programme.
Spain delivered the message to US Ambassador James Costos, summoned to explain the latest revelations in a growing scandal over US snooping on telephone and online communications of citizens and world leaders including German Chancellor Angela Merkel.
The NSA denied German press reports that President Barack Obama was informed in 2010 that US spies were tapping Merkel's mobile phone.
And National Security Council spokeswoman Caitlin Hayden said US intelligence gathering was simply "of the type gathered by all nations".
The news in Spain emerged just as a European parliament delegation was to begin a three-day mission to Washington to probe the impact of the surveillance on EU citizens' "fundamental rights" and to discuss a request to suspend an EU-US agreement on the transfer of bank data.
Spanish foreign ministry officials met with the US envoy hours after daily newspaper El Mundo published a classified document purportedly showing that the US security services tracked 60.5 million Spanish telephone calls in a single month.
The National Security Agency recorded the origin and destination of the calls and their duration but not the content, said El Mundo, which printed a classified graph showing 30 days of telephone call-tracing up to January 8 this year.
The graph illustrated the daily volume of calls traced in the period, peaking at 3.5 million on a single day, December 11.
Though not shown on the graph, the newspaper said such systematic trawling of huge volumes of digital information - or metadata - would include intercepting personal details through internet browsers, e-mails and social networks such as Facebook and Twitter.
The article was jointly authored by US blogger Glenn Greenwald, who said he had access to documents obtained by former US intelligence contractor Edward Snowden.