A bill to fund the Department of Homeland Security failed to advance on Friday in the Senate amid growing concerns about long lines to get through screening at some of the country’s biggest airports.

Democrats declined to provide the support needed to move the funding measure toward final passage. Senate Democratic leader, Chuck Schumer, said he would offer an alternative measure on Saturday to fund just the Transportation Security Administration, which screens passengers and luggage for hazardous items. That too is likely to fail as lawmakers hold a rare weekend session.

Behind the scenes, work toward resolving the standoff intensified Fon riday as White House border czar Tom Homan met for the second consecutive day with a bipartisan group of senators. Democrats are demanding changes to immigration enforcement practices by federal agents following the shooting deaths of Alex Pretti and Renee Good in Minneapolis.

Democratic lawmakers did not comment as they left the meeting with Homan. Senator Susan Collins, the Republican chair of the Senate appropriations committee, said the White House has added to its offer in hopes of resolving the standoff, but declined to go into specifics.

“It’s a very fair, reasonable offer,” Collins said, adding she hoped the two sides would meet again on Saturday. “But that depends on whether the Democrats come back with a response.”

Senate majority leader John Thune, said that he sees “deal space” coming out of the discussions with the White House. But he also questioned whether Democrats were serious about reaching any agreement that would provide more money for Immigration and Customs Enforcement.

“This is a pox on everybody’s house,” Thune said. “You’ve got people standing in lines at the airports. This needs to be fixed. It needs to get resolved and there are good-faith efforts being made finally on all the relevant issues.”

On the Senate floor, Schumer said he agreed that TSA needs to be reopened as quickly as possible – but not under the terms Republicans are offering, which is to fund the entire homeland security department. Democrats are looking to fund TSA while continuing negotiations on Immigration and Customs Enforcement.

“Tomorrow, America will see the matter crystal clear: which senators want to open up TSA, pay TSA workers, and end the chaos at our airports, and which senators are going to block TSA funding yet again,” Schumer said.

The vast majority of employees at TSA are considered essential and continue to work during the government funding lapse, but they are doing so without pay. Call-out rates have started to increase at some airports, leading to longer screening times for many passengers.

Democrats have demanded an array of policy changes as part of a funding bill that include requiring ICE agents to get a warrant from a judge before forcefully entering homes. They also are looking to require agents to wear identifying information on their uniforms and ban the use of masks.

“The American people have had enough of this rogue agency. We need to rein it in. And we are negotiating right now over how to do that,” said senator Patty Murray, the ranking Democrat on the Senate appropriations committee.

The Trump administration says it has agreed to several changes already, including expanded use of body-worn cameras, with an exception for undercover operations, and limited civil enforcement activities at certain sensitive locations, such as hospitals, schools and places of worship. Republicans also note that Trump has fired homeland security secretary Kristi Noem and put Homan in charge of operations in Minneapolis, actions they say show the administration’s intent to make changes in ICE’s operations.

Congress is scheduled to go on an extended break near the end of the month for a two-week Easter recess. Thune has threatened to keep senators in Washington if the impasse is not resolved.

“I can’t see us taking a break if the government is still shut down,” Thune said.