WASHINGTON (NewsNation) — A deal to provide further U.S. assistance to Ukraine by year-end appears to be increasingly out of reach for President Joe Biden. The impasse in Congress comes despite warnings from the White House about the consequences of inaction as Republicans insist on paring the aid with changes to immigration and border politics.

U.S. aid to Ukraine has nearly dried up, prompting the White House to announce that Biden will take a more active role in negotiations with lawmakers, focusing primarily on immigration talks as Congress heads into the holiday break this week.

Biden aims to secure tens of billions for Ukraine in its fight against Russia and Israel for the war with Hamas. However, Republicans insist on U.S. southern border changes in exchange, such as raising asylum standards, restricting humanitarian admission and expanding expedited removals.

Biden has said he’s willing to make “significant compromises on the border” as Republicans block the wartime aid in Congress.

Republicans argue for more comprehensive border crisis solutions. They say the record numbers of migrants crossing the southern border pose a security threat because authorities cannot adequately screen all the migrants and that those who enter the United States are straining the country’s resources. GOP lawmakers also say they cannot justify to their constituents sending billions of dollars to other countries, even in a time of war, while failing to address the border at home.

“It is literally spiraling out of control. All we’re trying to do is say what tools are needed to get this back under control, so we don’t have the chaos on our southern border,” Republican Sen. James Lankford of Oklahoma said Sunday on CBS.

Meanwhile, Democrats expressed frustration about linking border changes to Ukraine aid. They say some of the changes being proposed would gut protections for people who desperately need help and would not ease the chaos at the border.

“Vladimir Putin is delighting right now in Republicans’ insistence that we get a deal on immigration reform, and if we don’t, then they are going to allow Vladimir Putin to march into Ukraine and perhaps into Europe,” Connecticut Sen. Chris Murphy said on NBC’s ”Meet the Press.”

These negotiations follow a record number of encounters along the southern border in fiscal year 2023, with October showing an increase compared to the previous year, according to U.S. Customs and Border Protection data.

The Biden administration warns that U.S. aid to Ukraine might run out by the end of the year. Thursday marks a deadline for lawmakers: It’s the last day of business of the year for the House.