WASHINGTON (NEXSTAR) — Federal law enforcement agencies say a surveillance program known as FISA is critical to their investigations but portions of the program are now in limbo.

After years of supporting the Foreign Intelligence Surveillance Act, Republicans like Louisiana Congressman Steve Scalise are now blocking the re-authorization of three FISA surveillance programs that expired in March.

“I have been a strong supporter of the FISA court and its ability to properly help maintain the security of our country but the FISA process was abused,” Scalise said.

Republican support quickly melted away after President Trump said he would veto the re-authorization.

“The commitment to national security disappeared by a tweet,” said House Speaker Nancy Pelosi (D-CA). “A twinkle of a tweet, as they say.”

The move forced Pelosi to scrap a planned vote.

House Minority Leader Kevin McCarthy (R-CA) addressed Trump’s concerns that FISA was used to spy on his 2016 presidential campaign.

“It was used for surveillance on Americans,” McCarthy said.

But the re-authorization of the surveillance programs — which include the Patriot Act — also faces opposition from progressive Democrats who say there aren’t enough safeguards for Americans.

Oregon Senator Ron Wyden opposed the House re-authorization and says any renewal needs to include stronger protections against collecting Americans’ web browsing history without a warrant.

Now lawmakers are stuck trying to hammer out a compromise that pleases both the president and the law enforcement agencies that say FISA surveillance is critical to keeping the U.S. safe.