A critical U.S. surveillance program is heading toward expiration on Saturday after House Democrats blocked an extension of FISA Section 702, according to congressional sources.

The Foreign Intelligence Surveillance Act's Section 702 provision allows U.S. intelligence agencies to collect communications of foreign targets without a warrant. The program has been credited by intelligence officials with disrupting various security threats, including a recently thwarted terror plot targeting Taylor Swift concerts.

The legislative impasse comes amid broader tensions over intelligence oversight and surveillance authorities. The program requires periodic congressional reauthorization to continue operating legally.

Without an extension, the surveillance program would lapse, potentially affecting ongoing intelligence operations. Intelligence agencies have previously argued that Section 702 is essential for national security and counterterrorism efforts.

The timing of the expiration coincides with ongoing political disputes over intelligence oversight and surveillance powers. Congressional leaders have not announced plans for emergency sessions to address the impending deadline.

The program's supporters argue it provides crucial intelligence capabilities, while critics have raised concerns about potential domestic surveillance overreach and civil liberties protections.