WASHINGTON - The United States Monday said it must better weigh the risks and rewards of its spying activities, as Europe fulminates over reports it eavesdropped on German Chancellor Angela Merkel and other world leaders.
In its most comprehensive response yet to the allegations, albeit using heavily nuanced language, the White House said that the fact it had the technical expertise to carry out certain espionage missions, did not mean that it should.
"With new capabilities, we recognise that there needs to be additional constraints on how we gather and use intelligence," White House spokesman Jay Carney said.
Earlier, President Barack Obama's national security advisor Susan Rice wrote on Twitter that Washington was seeking a "proper balance between security concerns of our citizens and allies and the privacy concerns that all people share."
The comments followed a Wall Street Journal article which quoted unnamed senior officials as saying that Obama did not know US spies were bugging Merkel's cellphone and that when he found out, he ordered it stopped.
The more conciliatory language also came as the Obama administration prepares to meet two teams sent from Europe to discuss the diplomatic fallout from the claims, one from the European parliament, another including senior German government and intelligence agency officials.
New allegations meanwhile that US spy agencies tracked 60.5 million Spanish telephone calls in a single month led to more embarrassing exchanges between Washington and a European ally.
The White House stuck to its refusal to discuss the case of Merkel and other alleged operations specifically, but did speak in a way that may be designed to appease allies over National Security Agency (NSA) activities.