WASHINGTON — The Obama administration this morning defended the National Security Agency’s need to collect telephone records of U.S. citizens, calling such information “a critical tool in protecting the nation from terrorist threats.”

While defending the practice, a senior administration official did not confirm a newspaper report that the NSA has been collecting the telephone records of millions of U.S. customers of Verizon under a top secret court order.

The order was granted by the secret Foreign Intelligence Surveillance Court on April 25 and is good until July 19, Britain’s Guardian newspaper reported Wednesday. The order requires Verizon, one of the nation’s largest telecommunications companies, on an “ongoing, daily basis” to give the NSA information on all telephone calls in its systems, both in the U.S. and between the U.S. and other countries.

The administration official anonymously said, “On its face, the order reprinted in the article does not allow the government to listen in on anyone’s telephone calls.”

The newspaper said the document, a copy of which it had obtained, shows for the first time that under the Obama administration the communication records of millions of U.S. citizens were being collected indiscriminately and in bulk, regardless of whether they were suspected of any wrongdoing.

Verizon spokesman Ed McFadden said Wednesday the company had no comment. The NSA had no immediate comment.

Verizon Communications Inc. listed 121 million customers in its first-quarter earnings report this April — 98.9 million wireless customers, 11.7 million residential phone lines and about 10 million commercial lines. The court order didn’t specify which type of phone customers’ records were being tracked.