In a move likely to re-ignite public debate in America over electronic spying, Republicans have introduced a bill in the Senate to extend a controversial law empowering the government's bulk collection of U.S. telephone records.
President Barack Obama and many in Congress want to retain the mass data-collection program as a national security tool but want substantial changes in the program, which was secret until disclosed two years ago by former NSA contractor Edward Snowden.
Senate Majority Leader Mitch McConnell is sponsoring a bill to extend until Dec. 31, 2020, a provision of the USA Patriot Act that the National Security Agency used to collect and store vast quantities of "metadata" charting telephone calls made by Americans. The law is due to expire on June 1.
Republicans said they would expedite Senate consideration of McConnell's bill, which was submitted late on Tuesday, by sending it directly to the Senate floor rather than considering it first in committee.
Richard Burr, the Republican chairman of the Senate Intelligence Committee, acknowledged that prospects for the bill's passage were uncertain but said it would establish the parameters for debate.
The NSA program to collect and analyze telephone metadata was authorized by Congress after the Sept. 11, 2001, attacks.
It collected information about which U.S. phone numbers called other numbers and how long calls lasted, not their content. It was roundly condemned by civil liberties groups as an invasion of privacy.
A panel Obama appointed found no evidence it ever led to a counter-terrorism breakthrough.
In the wake of Snowden's revelations, Obama ordered the scope of the program to be limited and said he wanted the law reformed to have the data stored by telephone companies. The companies are resisting such a change.
Several experts said McConnell's bill would extend the existing law without modifying it as Obama wanted.
The White House declined comment.
Former intelligence officials said Obama could face heavy pressure to sign the type of bill McConnell introduced to avoid being blamed for an attack if he vetoed such a measure and the program was allowed to end.
Senator Patrick Leahy, the top Democrat on the Senate Judiciary Committee, said he would oppose any reauthorization that did not include significant reforms.
In a statement, the American Civil Liberties Union urged Congress to let the current law expire on June 1.
(Reporting by Mark Hosenball and Patricia Zengerle; Editing by David Storey and Cynthia Osterman)