EU leaders say their relations with the US have been undermined by reports of NSA spying on European leaders and ordinary citizens. A partnership with America should be built on respect and trust, they said in a joint statement.

The statement was released on Friday amid the ongoing summit of top European politicians in Brussels. It said the reports of American surveillance in Europe have raised “deep concerns” among the citizens and may harm cooperation between the EU and the US, particularly in counter-terrorism.

"[The leaders] stressed that intelligence gathering is a vital element in the fight against terrorism,” the statement said as cited by BBC. “A lack of trust could prejudice the necessary cooperation in the field of intelligence gathering."

Earlier German Chancellor Angela Merkel, whose phone had been reportedly bugged by American digital spies, warned that European countries’ relations with the US have been "severely shaken" by the developing scandal and that "trust needs to be rebuilt."

"The United States of America and Europe face common challenges. We are allies. But such an alliance can only be built on trust," she said. "That's why I repeat again: spying among friends, that cannot be." 

Over the week a number of reports on alleged American electronic surveillance have been released by various media outlets. The US National Security Agency was said to be spying on French and Italians, have wiretapped phones of 35 unidentified world leaders under the Bush administration, and particularly eavesdrops on Merkel.

The German leader is said to have a personal distaste for being spied on due to her experience in Communist Eastern Germany, where the nation’s notorious Stasi secret police had her under surveillance along with thousands of other Germans.

Spain leaders were also apparently targeted, according to reports from El Pais, the country’s most highly circulated paper.

The Spanish Government fears that current Prime Minister Mariano Rajoy and his predecessor Luis Rodriguez Zapatero were among those officials targeted by the NSA.

José Manuel García-Margallo y Marfi, Spain’s Minister for Foreign Affairs, previously said he would speak with US Ambassador James Costos as soon as there was confirmation regarding the issue. On Friday, Spanish Prime Minister Mariano Rajoy said  he would call in ambassador Costos to Madrid to explain reports of American spying on the country, AFP reports. 

"We do not have evidence that Spain has been spied on ... but we are calling in the ambassador to get information," Rajoy said after an EU summit which was dominated by the growing scandal that  US intelligence targets ostensibly friendly countries.

European concerns over American surveillance are not shared by every member of the EU. Denmark’s Prime Minister Helle Thorning-Schmidt told the media she doesn’t believe that she or her citizens have been targeted by the NSA, so she would not support a French-German initiative for starting a dialogue with the US to find a new ground in the surveillance issue. 

Amid the surveillance scandal, the European Parliament this week called for a suspension of America’s access to the SWIFT database, which contains millions of financial messages detailing exchanges around the world. The move is symbolic rather than binding.

But Europeans and some other countries elsewhere in the world are also seeking to toughen up data protection laws in the wake of the revelation of the scale of NSA surveillance.

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