BERLIN -- The German magazine Der Spiegel says the U.S. National Security Agency secretly monitored the U.N.'s internal video conferencing system by decrypting it last year.

The weekly said Sunday that documents it obtained from American leaker Edward Snowden show the NSA decoded the system at the U.N.'s headquarters in New York last summer.

Quoting leaked NSA documents, the article said the decryption "dramatically increased the data from video phone conferences and the ability to decode the data traffic."

In three weeks, Der Spiegel said, the NSA increased the number of decrypted communications at the U.N. from 12 to 458.

Snowden's leaks have exposed details of the United States' global surveillance apparatus, sparking an international debate over the limits of American spying.

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  • Sen. Dianne Feinstein (D-Calif.)

    Sen. Dianne Feinstein (D-Calif.) said the court order for telephone records was part of a three-month renewal of an ongoing practice, <a href="http://www.huffingtonpost.com/huff-wires/20130606/us-nsa-phone-records-feinstein/" target="_blank">the Associated Press reported</a>. "It’s called protecting America," Feinstein said at a Capitol Hill news conference.

  • Sen. Mark Udall (D-Colo.)

    Sen. Mark Udall (D-Colo.) <a href="http://www.huffingtonpost.com/2013/06/06/verizon-phone-records-nsa_n_3397058.html?utm_hp_ref=politics" target="_blank">said</a> "the administration owes the American public an explanation of what authorities it thinks it has."

  • Senate Majority Leader Harry Reid (D-Nev.)

    Senate Majority Leader Harry Reid (D-Nev.) thought everyone "should just calm down." "Right now I think everyone should just calm down and understand this isn't anything that's brand new," Reid <a href="http://www.huffingtonpost.com/2013/06/06/verizon-phone-records-nsa_n_3397058.html?utm_hp_ref=politics" target="_blank">said</a>.

  • Former Vice President Al Gore

  • Sen. Jeff Merkley (D-Ore.)

    Sen. Jeff Merkley (D-Ore.) said in a statement: "This type of secret bulk data collection is an outrageous breach of Americans’ privacy."

  • Sen. Lindsey Graham (R-S.C.)

    Sen. Lindsey Graham (R-S.C.) said he was <a href="http://www.huffingtonpost.com/2013/06/06/lindsey-graham-nsa_n_3396223.html?1370532449" target="_blank">"glad" the NSA was collecting phone records. </a> "I don’t mind Verizon turning over records to the government if the government is going to make sure that they try to match up a known terrorist phone with somebody in the United States," Graham said in an interview on "Fox and Friends."

  • Sen. Saxby Chambliss (R-Ga.)

    Sen. Saxby Chambliss (R-Ga.) also claimed that reports of the NSA collecting phone records was "nothing particularly new." "Every member of the United States Senate has been advised of this," Chambliss<a href="http://www.huffingtonpost.com/2013/06/06/verizon-phone-records-nsa_n_3397058.html?utm_hp_ref=politics" target="_blank"> said</a>. "And to my knowledge we have not had any citizen who has registered a complaint relative to the gathering of this information."

  • Sen. Bob Corker (R-Tenn.)

    Sen. Bob Corker (R-Tenn.) found the NSA collecting phone records <a href="http://www.huffingtonpost.com/2013/06/06/verizon-phone-records-nsa_n_3397058.html?utm_hp_ref=politics" target="_blank">"troubling."</a> "The fact that all of our calls are being gathered in that way -- ordinary citizens throughout America -- to me is troubling and there may be some explanation, but certainly we all as citizens are owed that, and we're going to be demanding that," Corker <a href="http://www.huffingtonpost.com/2013/06/06/verizon-phone-records-nsa_n_3397058.html?utm_hp_ref=politics" target="_blank">said</a>.

  • Sen. Ted Cruz (R-Texas)

  • Sen. Mike Lee (R-Utah)