U.S. Ambassador to Spain James Costos, center, leaves the Foreign Ministry after being summoned to a meeting with Spain's European secretary of state in Madrid on Monday. Juan Medina/Reuters

The National Security Agency (NSA) recently tracked more than 60 million phone calls in Spain within a month, Spanish newspaper El Mundo said Monday, citing a document reportedly obtained from former security contractor Edward Snowden.

Spain's government has said it was not aware its citizens had been spied on by the NSA, which has also been accused of accessing tens of thousands of French phone records and monitoring the phone of German Chancellor Angela Merkel.

El Mundo on Monday reproduced a graphic that it said was an NSA document showing the agency had spied on 60.5 million phone calls in Spain from Dec. 10, 2012, to Jan. 8 of this year.

It came a week after Le Monde reported similar allegations of U.S. spying in France and German magazine Der Spiegel reported that a document shows that the NSA tapped Merkel's mobile phone.

On Monday, the White House acknowledged that some changes could be afoot in Washington.

"We recognize there needs to be additional constraints on how we gather and use intelligence," said White House spokesman Jay Carney.

A statement issued Monday by Senate Intelligence Committee Chairman Dianne Feinstein, D-Calif., read: "It is abundantly clear that a total review of all intelligence programs is necessary so that members of the Senate Intelligence Committee are fully informed as to what is actually being carried out by the intelligence community."

El Mundo's report said the NSA monitored the numbers and durations of Spaniards' phone calls but not their content. It said the metadata system used by the NSA could also monitor emails and phone texts, although those were not shown on the graphic.

The newspaper said it reached a deal with Glenn Greenwald, the Brazil-based journalist who has worked with other media on information provided to him by whistle-blower Snowden, to get access to documents related to Spain.

Spanish Prime Minister Mariano Rajoy on Friday summoned U.S. Ambassador James Costos, who went to the Foreign Ministry on Monday. But Rajoy insisted that his government was unaware of any cases of U.S. spying on Spain.

Spain resisted calls from Germany for the European Union's 28 member states to reach a no-spy deal, similar to an agreement Berlin and Paris are seeking, though Rajoy said the country was looking for more information.

"We'll see once we have more information if we decide to join with what France and Germany have done," he told a news conference in Brussels on Friday.

"But these aren't decisions which correspond to the European Union but questions related to national security and exclusive responsibility of member states. France and Germany have decided to do one thing, and the rest of us may decide to do the same or something else."