Funding for the military has become a key issue in reaching a deal to raise the nation’s borrowing limit and avoid a catastrophic default, with Republicans pushing to prevent the Defense Department from having spending limits and making deeper cuts in national programs like education.

President Biden has resisted that demand, pointing to a long series of previous budget deals that cut or increased military spending along with discretionary programs outside of defense.

How the parties resolve that issue will be critical to the final outcome of any debt agreement. It remains possible that in order to reach a deal that avoids a default, Democrats will agree to a deal that allows military spending to grow even as non-defense spending falls or remains flat.

Biden’s advisers and congressional Republicans, delegated by President Kevin McCarthy, are trying to broker a deal to lift the debt limit before the government runs out of money to pay its bills on time, which could happen on June 1. Republicans have refused to raise the cap unless Mr. Biden agrees to cuts in federal spending outside of the military.

Talk of spending cuts has narrowed to mostly cover a relatively small part of the budget, known as discretionary spending. That expense is divided into two parts. One is money for the military, which the Congressional Budget Office estimates will total $792 billion for the current fiscal year. The other half funds a wide range of national programs, such as Head Start Pell Grants for preschool and college, and federal agencies such as the Departments of the Interior and the Department of Energy. It will have a total of $919 billion this year, the budget office estimates.

A separate category known as mandatory spending has been largely considered off-limits in the talks. That spending, which is the main driver of future spending growth, includes programs like Social Security and Medicare.

Administration officials have proposed freezing both halves of discretionary spending for next year. That would amount to a budget cut, compared to projected spending, in the way the budget office accounts for spending levels. Spending for both parts of the discretionary budget would be allowed to grow by just 1 percent for fiscal year 2025. That, too, could amount to a budget cut since 1 percent would almost certainly be less than the rate of inflation. That proposal would save about $1 trillion over the course of a decade, compared with current budget office forecasts.

Republicans rejected that plan at the negotiating table. They are pushing to cut non-defense spending in nominal terms, that is, spending fewer dollars next year than the government spent this year. They also want to allow military spending to continue to grow.

“It just sends a bad message and Republicans feel like it wouldn’t be in our best interest to cut spending right now, when you look at China and Russia and a lot of instability around the world,” said Rep. Robert B. Aderholt, Republican of Alabama. , who is part of an Appropriations panel that oversees Pentagon spending. “That has been the basic position that most Republicans have.”

Mr McCarthy issued a similar note when speaking to reporters on Thursday. “Look, we’re always looking for where we can find savings and stuff, but we live in a very dangerous world,” he said. He added: “I think the Pentagon has to have more resources.”

Republicans included 10-year caps on discretionary spending in a bill they passed last month that also raised the debt ceiling to next year, and party leaders said they would exempt the military from those caps. Biden has promised to veto the bill if it passes the Senate in its current form, which is unlikely.

White House officials have criticized Republicans for concentrating their proposed discretionary savings on domestic programs, saying their bill would cut spending on border control, care for some veterans, Meals on Wheels for older Americans and a host of others. popular programs.

“House Republicans have been very clear about how they see the future and the cuts that they have tabled, those 22 percent cuts to veterans and health care and public safety, are going to hurt American families,” Karine Jean-Pierre, the White House press secretary, said this month.

Democrats in Congress, including members of committees that oversee military spending, have attacked Republicans for focusing primarily on non-defense programs.

“If you’re going to freeze discretionary spending, there’s no reason defense shouldn’t be a part of that conversation,” said Rep. Adam Smith of Washington, the top Democrat on the Armed Services Committee. The Republicans, he said, “are taking a hostage to advance their very limited agenda. I’m not a fan of that. That’s not something I’m going to want to support.”

Any deal that would increase military spending while freezing or cutting other discretionary spending would break with a tradition of budget deals that dates back to 2011, when House Republicans refused to raise the debt limit until President Barack Obama agreed to the terms. spending cuts. The deal that prevented default focused on spending caps that divide your reductions equally between advocacy and non-advocacy programs.

The push to increase military funding while cutting more elsewhere reflects a split in the House Republican caucus. It includes a large faction of defense hawks who say the military budget is too small, along with another large faction of spending hawks who want to significantly reduce the federal government’s fiscal footprint.

McCarthy needs both factions to retain control of the presidency, which he narrowly won this year after a marathon week of efforts to secure votes. And he will have to navigate both as he tries to pass any debt limit deal with Mr. Biden through the House.

catie edmondson contributed reporting.