The US National Security Agency (NSA) has temporary lost its authority to collect bulk phone records.
The surveillance programme made public by Edward Snowden expired this morning (June 1).
The Senate voted 77-17 to move ahead on an updated, reformed programme, the USA Freedom Act, which would not come into effect just yet.
Senator Rand Paul stood in the way of extending the old one in the meantime, calling it illegal.
“Are we going to so blithely give up our freedom?,” asked the Republican presidential candidate. “Are we going to so blithely go along and just say take it? Well, I’m not going to take it anymore. I don’t think the American people are going to take it anymore.”
Civil liberties groups applauded as Paul, who is running for president, forced the expiration of the once-secret programme made public by NSA contractor Edward Snowden.
Intelligence officials warned that the surveillance lapse could jeopardise the safety of Americans and amount to a win for extremists.