WASHINGTON (AP) — A bill that would reauthorize a crucial national security surveillance program was blocked Wednesday by a conservative revolt, pushing the prospects of final passage into uncertainty amid a looming deadline. The legislative impasse follows an edict earlier in the day from former President Donald Trump to "kill" the measure.

The breakdown comes months after a similar process to reform and reauthorize the surveillance program fell apart before it even reached the House floor. Speaker Mike Johnson, R-La., has called the program "critically important" but has struggled to find a path forward on the issue, which has been plagued by partisan bickering for years. The procedural vote to bring up the bill Wednesday failed 193-228, with nearly 20 Republicans voting no.

It marks the latest blow to Johnson's leadership as he faces being ousted from his job in the same stunning fashion as his predecessor. Hours before the vote, the Republican leader made a final push urging for passage, saying Congress must "address these abuses" without cutting off the surveillance program entirely.

"It's a critically important piece of our intelligence and law enforcement in this country," he said in a press conference.

The bill in question would renew Section 702 of the Foreign Intelligence Surveillance Act, which permits the U.S. government to collect without a warrant the communications of non-Americans located outside the country to gather foreign intelligence. The reauthorization is currently tied to a series of reforms aimed at satisfying critics who complained of civil liberties violations against Americans.

But Republican opponents have complained that those changes did not go far enough. Among the detractors are some of Johnson's harshest critics, members of the ultra-conservative House Freedom Caucus, who have railed against the speaker for reaching across the aisle several times since taking the gavel in October to carry out the basic functions of the government.

It remains unclear now if the proposal, backed by the Biden administration and Johnson, would eventually have enough votes to advance.

"I'm just bewildered that a small number of members decided to take down the rule," Rep. Jim Himes of Connecticut, the top Democrat on the House Intelligence Committee, told reporters on Wednesday evening.

The panel's Republican chairman, Mike Turner of Ohio, also lamented that the bill had faltered, especially since he said it had unanimous support from a special working group.

"There's a great deal of misinformation about FISA," Turner said. "It is not spying on Americans — in fact, that is absolutely prohibited."

Though the program would technically expire on April 19, the Biden administration has said it expects its authority to collect intelligence to remain operational for at least another year, thanks to an opinion earlier this month from the Foreign Intelligence Surveillance Court, which receives surveillance applications. But administration officials also say that if the program lapses, some telecommunications companies could reduce or stop cooperation with the government or challenge its authority.

U.S. officials have said the tool, first authorized in 2008 and renewed several times since then, is crucial in disrupting terror attacks, cyber intrusions and foreign espionage and has also produced intelligence that the U.S. has relied on for specific operations.

But the administration's efforts to secure reauthorization of the program have encountered fierce, and bipartisan, pushback, with Democrats like Sen. Ron Wyden who have long championed civil liberties aligning with Republican supporters of Trump, who in a post on Truth Social on Wednesday stated incorrectly that Section 702 had been used to spy on his presidential campaign.

"Kill FISA," Trump wrote in all capital letters. "It was illegally used against me, and many others. They spied on my campaign." A former adviser to his 2016 presidential campaign was targeted for surveillance over potential ties to Russia under a different section of the law.

A specific area of concern for lawmakers has centered on the FBI's use of the vast intelligence repository to search for information about Americans and others in the U.S. Though the surveillance program only targets non-Americans in other countries, it also collects communications of Americans when they are in contact with those targeted foreigners.

In the past year, U.S. officials have revealed a series of abuses and mistakes by FBI analysts in improperly querying the intelligence repository for information about Americans or others in the U.S, including about a member of Congress and participants in the racial justice protests of 2020 and the Jan. 6, 2021, riot at the U.S. Capitol.

Those violations have led to demands for the FBI to have a warrant before conducting database queries on Americans, which FBI director Chris Wray has warned would effectively gut the effectiveness of the program and would also be legally unnecessary given that the information in the database has already been lawfully collected.

"While it is imperative that we ensure this critical authority of 702 does not lapse, we also must not undercut the effectiveness of this essential tool with a warrant requirement or some similar restriction, paralyzing our ability to tackle fast-moving threats," Wray said in a speech Tuesday.