New secret documents allegedly stolen from the U.S. National Security Agency by Edward Snowden show how closely German intelligence cooperates with the NSA, despite the German government's harsh criticism of American surveillance, according to a major German newspaper.

The documents, as reported by Germany's Der Spiegel, describe how the NSA gave Germany one of its spying programs, called XKeyscore, and a trip in which NSA experts briefed German intelligence officers in a "strategic planning conference" at NSA headquarters on American surveillance capabilities.

According to Der Spiegel, educational slides about XKeyscore reveal the program is designed to absorb a "full take" of unfiltered data, including at least part of the contents of communications, for days and makes it possible to retroactively search for key words that may have been entered into online search engines or for locations searched on Google Maps.

Additionally, the NSA documents reportedly reveal an NSA officer, officially known as a diplomat at the U.S. Embassy in Berlin, regularly uses a desk at the headquarters of a German intelligence agency.

FULL STORY: The Secret Link Between Germany and the NSA (Der Spiegel)

The Der Spiegel report comes three weeks after German leader Angela Merkel blasted the U.S. for its alleged spying on the European Union.

"The monitoring of friends - this is unacceptable. It can't be tolerated," Merkel said then through a spokesperson. "We are no longer in the Cold War."

READ: E.U. to Sweep for Bugs Amid New U.S. Spying Claims

Edward Snowden, a former NSA contactor who fled the U.S. with a trove of secret documents, remains holed up in a Moscow airport from which he reportedly applied for temporary political asylum in Russia. The Russian government has not given a formal answer to his application.

Russian President Vladimir Putin previously said Snowden would be allowed to stay, but only if he stops damaging American interests with further leaks. Snowden said he never intended to damage American interests and, besides, he's already given all his secret information to several journalists.

Snowden has been charged in the U.S. with espionage.