WASHINGTON – President Donald Trump asked Congress for $4.5 billion in emergency funds to address what he described as a "humanitarian crisis" at the U.S.-Mexican border, setting up another showdown with lawmakers over immigration.

The money would be used to handle an influx of migrants, not Trump's proposed border wall, according to administration officials who spoke on the condition of anonymity to discuss details of the proposal. The request is likely to run into opposition from Democrats concerned with the administration's overall approach to immigration.

"The situation becomes more dire each day," Russell Vought, acting director of the Office of Management and Budget, wrote to congressional leaders in the White House request. "The migration flow and the resulting humanitarian crisis is rapidly overwhelming the ability of the Federal Government to respond."

Democrats said they would review the request but raised concerns about some of the proposals. More than $150 million of the new money would be used to accommodate “significant increases” in immigrants detained, for instance.

“The Trump administration appears to want much of this $4.5 billion emergency supplemental request to double down on cruel and ill-conceived policies,” said Rep. Nita Lowey, D-N.Y., who chairs the House Appropriations Committee. “Locking up people who pose no threat to the community for ever-longer periods of time is not a solution to the problems at the border.”

The money, if approved, would be a major increase in funding for the border. Trump had sought $5.7 billion for the border wall, which resulted in a fight that led to the partial government shutdown this year. He wound up receiving $1.375 billion for border fencing. The White House said it will free up $8 billion through the national emergency Trump declared on the border in February.

Administration officials said the funding would be used to build facilities to house immigrants, medical treatment, food, diapers and similar needs. The Department of Homeland Security has been repeatedly criticized for conditions at the border.

The funding would include $3.3 billion for humanitarian assistance, $1.1 billion for border operations and $178 million for "mission support," the White House said.

Border Patrol agents apprehended more than 92,000 immigrants trying to cross the border illegally in March, a 12-year high. The administration is dealing with a surge of migrant families fleeing violence in Central America and attempting to claim asylum. The White House proposed sweeping rules this week that would make the asylum process more difficult and more expensive.

Trump has been carrying out a major shakeup at the Department of Homeland Security, including the removal of Secretary Kirstjen Nielsen last month.

Alabama Rep. Mike Rogers, the top Republican on the House Homeland Security Committee, pressed Democrats to support the request, describing it as “an opportunity for House Democrats to put down their partisan rhetoric and embrace the need for more DHS funding.”

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