WASHINGTON (AP) - The National Security Agency is losing its authority to collect Americans' phone records in bulk, after Republican Sen. Rand Paul stood in the way of extending the fiercely contested program in an extraordinary Sunday Senate session.

But that program and several other post-Sept. 11 counter-terror measures look likely to be revived in a matter of days. With no other options, Senate Majority Leader Mitch McConnell, in an about-face, reluctantly embraced a House-passed bill -- the USA Freedom Act -- that would extend the anti-terror provisions that expire Sunday at midnight, while also remaking the bulk phone collections program.

Although the lapse in the programs may be brief, intelligence officials are warning that it could jeopardize Americans' safety and amount to a win for terrorists. But civil liberties groups are applauding Paul, who is running for president. Critics of the bulk collection program say it is an unconstitutional intrusion into Americans' privacy.