Senior White House officials on Wednesday warned lawmakers against turning to a possible fallback measure that would temporarily make legal a program that protects nearly 700,000 undocumented immigrants from deportation.

It appears a longshot that the House and Senate will both pass immigration overhaul bills that address the Obama-era Deferred Action for Childhood Arrivals, or DACA, program and reconcile differences ahead of a March 5 deadline for its termination. One option should Congress fail to act by that date would be a measure legalizing DACA temporarily as members keep trying to strike a broader deal.

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One senior White House official, however, told reporters that President Donald Trump would view such a short-term DACA measure — which likely would also include some enhanced border security measures — as “insufficient.”

Another senior official said Trump already gave Congress six months of “leeway” to come up with an immigration measure that would legalize DACA when he signed an executive order in September setting it on a path to termination on March 5 unless he was given a bipartisan bill to sign into law. 

Adding to the drama, federal court orders, including one issued Tuesday, are largely blocking the president from ending the immigration program, making the March 5 deadline somewhat flexible.

The officials, on a hastily arranged conference call, also doubled down on Trump’s endorsement of a Senate immigration amendment released late Tuesday by Senate Judiciary Chairman Charles E. Grassley of Iowa.

“The Grassley bill accomplishes the four pillars of the White House Framework: a lasting solution on DACA, ending chain migration, cancelling the visa lottery, and securing the border through building the wall and closing legal loopholes,” Trump said in a statement released a few hours before officials briefed reporters.

“I am asking all senators, in both parties, to support the Grassley bill and to oppose any legislation that fails to fulfill these four pillars — that includes opposing any short-term ‘Band-Aid’ approach,” Trump said.

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Trump and congressional Republicans already have made concessions, including proposing to expand DACA protections to another 690,000 undocumented individuals brought here illegally by their parents but who have not registered for the program “for whatever reason,” one of the senior officials said Wednesday.

Another concession they cited is the White House’s endorsement of offering Dreamers a pathway to citizenship.

Meanwhile, the senior White House officials also tried to pressure Senate Democrats ahead of floor votes on immigration measures. They warned Democrats to “care more about Dreamers than donors,” charging the party with supporting immigration proposals that would keep businesses able to rely on cheap immigrant labor rather than paying American workers more.

They also accused Senate Democrats of being unwilling to compromise, with one of the senior officials asking rhetorically: “What concessions have Democrats made?”

Niels Lesniewski contributed to this report.