The CIA is paying AT&T more than $10 million a year to provide phone records for overseas counter-terrorism investigations, the New York Times reported, quoting government officials.

The No. 2 US mobile service provider is cooperating under a voluntary contract, not under subpoenas or court orders compelling the company to participate, the paper said.

AT&T did not confirm or deny the report but said payments from governments were routine for lawful data.

The report comes amid widespread political uproar after former National Security Agency contractor Edward Snowden leaked documents describing how the US government collects far more internet and telephone data than previously known.

Under the AT&T arrangement, the CIA supplies phone numbers of overseas terrorism suspects and AT&T searches its database to provide call records that may help identify foreign associates, the paper said.

Most of the call logs provided by AT&T involve foreign-to-foreign calls, the paper said.

AT&T does not disclose the identity of the Americans calling from the United States, and masks their phone numbers when it produces the records, the paper said, quoting the officials.

AT&T said all government data requests were handled in a lawful and proper manner.

"We ensure that we maintain customer information in compliance with the laws of the United States and other countries where information may be maintained," AT&T spokesman Mark Siegel said in an emailed statement.

"Like all telecom providers, we routinely charge governments for producing the information provided."