A US programme, which allows the National Security Agency (NSA) to store millions of phone calls made by Americans, is being investigated in Congress.
Members of a committee appointed by President Barack Obama have been testifying on the controversial use of metadata spying.
The panel found that there was no evidence that the NSA's mass surveillance had prevented any attacks.
But for some members of Congress, the question is whether President Obama will address the concerns raised by leaker Edward Snowden's documents on Friday.
Al Jazeera's Shihab Rattansi reports from Washington DC.
Source: Al Jazeera