The Obama administration acknowledged that it is collecting a massive amount of telephone records from at least one telephone carrier, saying it's necessary to protect Americans against attack.

The admission comes after the Guardian newspaper published a secret court order related to the records of millions of Verizon Communications customers on its website.

According to Reuters, "a senior administration official did not specifically confirm the report, but noted the published court order pertains only to data such as a telephone number or the length of a call, and not the subscribers' identities or the content of the telephone calls."

The order requires the government to turn over so-called "metadata" such as a list of numbers that called other U.S. or international numbers as well as other transactional information on the time and location of calls.

Such information is "a critical tool in protecting the nation from terrorist threats to the United States," Reuters said.

Verizon has declined to comment. It remains unclear clear whether the practice extends to other carriers.

AT&T Inc had no comment. Representatives for other major carriers, including Sprint Nextel Corp and T-Mobile, could not be immediately reached or had no immediate comment, Reuters said.

The three-month court order, dated April 25 and published by the Guardian, directs Verizon's Business Network Services Inc and Verizon Business Services units to hand over daily electronic data until July 19.

The order expressly compels Verizon to turn over both international calling records and domestic records, and refers to mobile and landline numbers, according to the Guardian's copy, which was labeled "top secret" and issued by the U.S. Foreign Intelligence Surveillance Court.

The order can be seen at: r.reuters.com/kap68t