WASHINGTON — House and Senate negotiators on Monday night agreed “in principle” to provide $1.375 billion for physical barriers at the southwestern border, according to two congressional aides. It is a figure far lower than the $5.7 billion that President Trump had demanded for a border wall.
The deal, which would stave off another partial government shutdown at midnight Friday, appears to be a significant victory for Democrats. It came together just before Mr. Trump was about to begin a campaign and “Finish the Wall” rally in El Paso. It still must pass the House and Senate, and secure Mr. Trump’s signature.
The negotiators also agreed to reduce the number of migrants and undocumented immigrants who can be held in detention.
It would allow for 55 miles of new bollard fencing, with some restrictions on location based on community and environmental concerns, according to the two aides, who requested anonymity to disclose details of the negotiations. The is a fraction of the hundreds of miles of steel-and-concrete wall that the president shut down the government over in December.
Democrats’ demand for a limit on how much detention space could be used for unauthorized immigrants arrested within the United States had threatened to derail the negotiations over the weekend, but lawmakers agreed to waive the demand.
Lawmakers announced they had reached the agreement after three private meetings on Monday. It is expected to be finalized as early as Tuesday, well before the Friday deadline when funding would again lapse for a number of federal agencies. With fears of another damaging shutdown, lawmakers seemed confident that they had the support of party leadership and that Mr. Trump would be willing to sign the agreement.
A specific point of contention had been the number of detention beds under the control of Immigration and Customs Enforcement.
Aides in both parties had warned that a final deal might leave the number of detention slots — or “interior beds” — unchanged, not reduced as Democrats want and not increased as Mr. Trump wants.
House Democrats, urged on by immigration rights groups, have pushed hard, hoping to leverage White House fears of another damaging shutdown into a softening of the president’s hard-line immigration policies that they say have torn apart families and infused a heartlessness into official American immigration policy.
The Democrats’ tool: limit the number of beds that ICE has to hold undocumented immigrants in custody to 16,500 from around 20,700.
The Democrats’ ultimate goal is to cut the overall number of detention beds, including those occupied by asylum seekers and people caught at the border, from its current level of around 49,000 to 34,000, the number funded during the Obama administration, Democratic aides said. That, they say, would end sweeps and roundups, and force ICE to focus on pursuing hardened criminals.
Last year, the Trump administration requested funding for 52,000.
With their number, Democrats say they can seize the initiative on immigration from a president who has staked his political fortunes on the issue.
“We started at zero on the wall, and we compromised a lot after that, and we are now asking them to change, too,” said Representative Lucille Roybal-Allard, Democrat of California and a member of the 17-member House and Senate conference committee tasked with hammering out a compromise.
Mr. Trump was catching on. When Senator Richard C. Shelby, Republican of Alabama and the chairman of the Appropriations Committee, presented him with the Democrats’ demand, he rejected it quickly, according to two people briefed on the exchange.
“These are people coming into our country that we are holding and we don’t want in our country,” the president told reporters at the White House late Monday. “That’s why they don’t want to give us what we call ‘the beds.’ It’s much more complicated than beds, but we call them from ‘the beds.’”
In private, Republicans responded with a plan that would exempt many detained immigrants from the cap, including those people either charged with or convicted of crimes, including misdemeanor drug offenses and violent felonies. That, in turn, was rejected by Democrats.
“You have ICE agents picking up mothers and fathers and children in their own neighborhoods. That’s why the beds issue is so much more important than the wall,” said Ms. Roybal-Allard, whose Los Angeles-area district is 85 percent Hispanic, the highest percentage of any district in the country.
The number of beds occupied by detainees fluctuates over time, influenced by a variety of factors, including ICE enforcement policies and the flow of migrants at the border with Mexico. The rate of that flow is unpredictable and determined by factors such as the performance of the economies north and south of the border, crime, gang activity and the business practices of coyotes paid to transport migrants from Mexico and Central America to California and the Southwest.
The number of monthly apprehensions of migrants at the border has averaged 25,000 to 40,000 for most of the past decade, but has risen to about 50,000 over the past several months, according to statistics compiled by the Department of Homeland Security.
If ICE does not have enough room to place individuals and family members they detain, they must loosen their enforcement actions, creating a powerful motive for new migrants to enter the country illegally, Trump administration officials say.
“You cannot have border security, without strong interior enforcement, whether there is a wall there or not,” said Matt Albence, the deputy director of ICE, on Monday in a conference call with reporters.
Republicans closed ranks to blast the plan.
“This is a poison pill that no administration, not this one, not the previous one, should ever accept,” said Senator Mitch McConnell, Republican of Kentucky and the majority leader, said on the Senate floor. “Imagine the absurdity of this: House Democrats want to set a limit on how many criminal aliens our government can detain.”
Earlier Monday, Democratic leadership aides said that there would be no deal without some concession on the bed issue — in part because immigrants rights groups and party liberals would revolt if they agreed to extend border barriers without getting something tangible in return.
Last Friday, when word of a possible deal first leaked out, advocates for immigrants reached out to Democratic leadership offices, including Speaker Nancy Pelosi’s, to say that they would oppose any deal that did not address their concerns about ICE.
“For the last two years, we have been trying to limit the bad. We have taken a defensive approach, but now House Democrats have the power to start doing some good,” said Lorella Praeli, the deputy national political director of the American Civil Liberties Union, one of the groups that has pressed the Democratic leaders, Ms. Pelosi of California and Senator Chuck Schumer of New York, to reject any deal that does not include steps to reduce aggressive immigration enforcement.
“It’s time for them to show that they are fighting for us,” Ms. Praeli added. “It means you have to do something more than a floor speech or a tweet supporting immigrants. It’s time to actually do something.”