A fight over defense funding is emerging as a key hurdle to getting a budget deal and avoiding across-the-board spending cuts.

Senators on Thursday battled over a Democratic push to equally increase defense and nondefense spending as Congress faces an upcoming deadline to lock down an agreement.

Senate Majority Leader Mitch McConnell (R-Ky.) said following a closed-door meeting between congressional leadership and the White House that he was “optimistic” a two-year agreement could be reached, but Democrats must set aside their demand.

{mosads}”Any agreement must provide our armed forces with the resources they need to fulfill their missions.That means setting aside the misguided notion that new defense spending needs to be matched dollar for dollar by new nondefense spending,” he said.

McConnell argued that the military had taken more of a hit under the Budget Control Act and the ongoing negotiations provided a “golden opportunity to put aside political calculations.”

Congress faces a mid-January deadline to both avoid a government shutdown and automatic across-the-board spending cuts under sequestration.

Negotiators have been meeting for weeks to try to lock down top-line spending numbers, but so far a deal has yet to crystallize.

Sen. Bernie Sanders (I-Vt.) fired back at McConnell, saying he is “disturbed” by the Republican leader’s comments, which he argues are “inaccurate and misleading.”

“The Republican Party, which controls the White House, the U.S. House and the U.S. Senate, is pushing us closer and closer to a very dangerous government shutdown,” he said.

Senate Minority Leader Charles Schumer (D-N.Y.), laying out Democratic priorities for a deal, added that the agreement “must lift spending caps with parity between defense and urgent domestic programs.”

“So I hear the majority leader say that he’s not for parity. Parity’s not a word. It’s veterans. It’s people who are needing opioid relief. It’s working-class folks,” he said.

In addition to battling over spending increases, Schumer added that the budget deal also needed to include disaster aid, a health-care package and “an agreement to enshrine DACA protections alongside additional border security.”

A group of Senate Republicans went to the White House on Thursday to get guidance from President Trump on what he would accept as part of a deal on the Deferred Action for Childhood Arrivals (DACA) program.

Democrats believe the looming funding deadlines give them leverage to get an immigration deal this month.

But McConnell on Thursday warned that Democrats shouldn’t hold other priorities “hostage.”

“If a compromise solution emerges that meets the president’s conditions, it will be brought up for a vote here in the Senate. In the meantime, let’s continue productive negotiations and secure a bipartisan funding agreement,” he said.