The US Senate has rejected a bill that would curb the country’s National Security Agency (NSA)’s bulk collection of telephone data, leaving it uncertain the fate of the once-secret program ahead of its expiration at the end of the month.

The bill, USA Freedom Act, which would have ended the NSA’s bulk collection but preserved its ability to search the records held by phone companies on a case-by-case basis, fell three votes short of the 60 votes needed for passage in the Senate on Saturday, Xinhua reported.

The bill, backed by President Barack Obama, the nation’s top law enforcement and intelligence officials, was passed overwhelmingly in the House of Representatives early this month.

After Senate’s rejection of the bill in the wee hours of Saturday, another attempt to extend the expiring provision of Patriot Act, which authorizes the NSA’s spying program, was also blocked in the Senate.

The disarray in Congress appeared to significantly increase the chances that the government will lose systematic access to newly created calling records by Americans, at least temporarily, after June 1.

The Senate will reconvene on May 31 to try again. But any extension is far from certain to get approval from the House, which is in recess until June 1, with at least one member threatening to block it.

Under the House bill, which passed 338 to 88, the Patriot Act would be changed to prohibit bulk collection by NSA of metadata charting telephone calls made by Americans. While the bill would take the government out of the collection business, it would not deny it access to the information.

The debate over the federal program became intense after the government’s extensive surveillance efforts were exposed by Edward Snowden, a former NSA contractor. It was complicated by a federal appeals court ruling this month that found the NSA’s bulk collection of phone records illegal.

The odd collection of advocates for change underscored a changing tide in post-Sept. 11 America, where privacy concerns have become as important as national security interests for many people.