A top American diplomat was caught cursing the European Union, but it’s how her comments were leaked that is raising questions.

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Victoria Nuland, assistant secretary for European and Eurasian Affairs, was reportedly on the phone with another U.S. diplomat talking about the crisis in Ukraine.

Nuland says in the recording, “That would be great, I think, to help glue this thing and have the U.N. help glue it. And you know, (expletive) the EU.”  

Massive protests began when Ukraine’s President Viktor Yanukovych​ aligned himself with the Russians rather than the EU. Fox News chief intelligence correspondent Catherine Herridge reported that Nuland's comments seemed to express frustration with the EU's lack of support for U.S. diplomatic efforts.

In response to the leaked call, Nuland raised questions about Russia’s spying capabilities. “I’m obviously not going to comment on private diplomatic conversations other than to say, it was pretty impressive trade craft. The audio was extremely clear."

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Intelligence officials told Fox News that this is spying 101 and that Nuland was likely not using a secure line. "When U.S. diplomats are overseas, especially in Russia, they have to assume that all of their conversations are being monitored," Herridge reported.

On Thursday, State Department spokesperson Jen Psaki apologized for the f-bomb. She would not confirm whether the voice on the recording belonged to Nuland.

The Associated Press reported that an aide to Russia’s deputy prime minister denied any Russian involvement in leaking the phone call:

A Russian government aide who was among the first to post a video online containing a bugged phone call between two U.S. diplomats denied Friday that he or the government played a role in leaking the recording.

Dmitry Loskutov said he was surfing a social networking website on Thursday when he came across the video, in which the top U.S. diplomat for Europe, Victoria Nuland, disparages the European Union.

Loskutov, an aide to Deputy Prime Minister Dmitry Rogozin, told The Associated Press in a telephone interview that his decision to repost the video had no connection to his work for the Russian government.

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