The Washington Post
claims U.S. officials are warning some foreign intelligence services that documents obtained by National Security Agency contractor Edward Snowden detail their secret cooperation with Washington.
According to the paper, the tens of thousands of documents that Snowden collected contain sensitive material about collection programs against such countries as Iran, Russia and China. The newspaper said the documents also referred to operations involving countries not publicly allied with the U.S.
The Washington Post
described the process of notifying world capital officials about the risk of disclosure as "delicate" because, in some cases, one part of a cooperating government might not know about the collaboration.
The notification coincides with a global uproar over reports the United States spied on the phone conversations of 35 world leaders. The latest report is about the possible bugging of German Chancellor Angela Merkel's cell phone.
European leaders have united behind a furious Germany to denounce the United States for allegations it spied on its allies.
On Thursday, White House spokesman Jay Carney refused to deny the NSA had spied on past communications from Chancellor Merkel.
Merkel says she made it clear in a phone call Wednesday to U.S. President Barack Obama that "spying on friends is not acceptable at all."
Before a 28-nation European Union summit meeting in Brussels, Merkel called for "trust among allies and partners. Such trust now has to be built anew."
Other European leaders arriving for the meeting echoed the German leader's displeasure.
European Union Commission President Jose Manuel Barroso objected to the the spying as a slide toward "totalitarianism."
Early Thursday, Germany's foreign minister summoned the U.S. ambassador to discuss the matter.
The Obama administration has denied news reports about many U.S. intelligence activities. Those reports stem from secret documents leaked by NSA contractor Edward Snowden, who is currently living in Russia.
White House officials have repeatedly said the intelligence gathered by the United States is the type "gathered by all nations."
President Obama has ordered a review of the way U.S. intelligence is gathered, in an effort he says is intended to ensure a proper balance of security concerns and privacy concerns.