Declan McCullagh/CNET

The National Security Agency reportedly contemplated curtailing its program to collect the phone records of America citizens even before whistleblower Edward Snowden spilled the beans.

The NSA, which has been intensely criticized for its program of vacuuming up the phone call records of US citizens, has publicly defended the practice as a necessary measure to combat terrorism. But months before the surveillance came to light in 2013 with the release of documents leaked by Snowden, a proposal to end the program was being discussed among top managers of the agency, current and former intelligence officials told the Associated Press.

NSA insiders who called for the program to be killed cited several factors, according to the AP's sources. The cost of capturing and storing records from every domestic landline was growing higher. The system wasn't grabbing the records of mobile phone calls. The program was not integral to discovering terrorist plots. And critics inside the agency were concerned about the reaction should the program ever become public knowledge.

The effort to halt the program never got beyond the discussion stage. The proposal never even reached then-NSA director Keith Alexander, officials told the AP. But even if it had, the officials said they doubt that Alexander would have called for a halt to it. Alexander has defended the program, arguing that its goal has been to protect the country and the safety of American citizens.

But in December 2013, a presidential task force that looked at the NSA's program recommended that the bulk data collection by the agency be stopped and that phone records instead be held by the phone companies or other third parties. The group also questioned the effectiveness of the program at the cost of the privacy of individuals.

"We cannot discount the risk, in light of the lessons of our own history, that at some point in the future, high-level government officials will decide that this massive database of extraordinarily sensitive private information is there for the plucking," the report said.

Currently, however, the NSA's bulk collection program continues. Last year, President Obama called for an end to the program as it stood at the time. But that proposal needs to be approved by Congress, which has yet to happen. The program itself is allowed under Section 215 of the Patriot Act, which is due to expire on June 1. And what happens if Congress fails to act before then?

The NSA and other agencies will be forced to stop their data collection unless Congress extends the law, U.S. officials said last Monday, according to Reuters. Congress remains divided over how to handle the law, with some arguing that it should be retired and others saying it should continue.

Ned Price, a spokesman for President Barack Obama's National Security Council, told Reuters the White House would stop the bulk data collection unless Congress reauthorizes it.

"If Section 215 (of the law which covers the collection) sunsets, we will not continue the bulk telephony metadata program," Price said.