Trump administration officials are holding closed-door meetings with top lawmakers to push a record-high $1.5 trillion Department of Defense budget through Congress. But a clash is looming with members of the president’s own party: fiscal hawks.

The dynamic, given House Speaker Mike Johnson’s razor-thin majority, threatens to scramble a defense budget aimed at ramping up munitions and ship production while raising troop pay — all key parts of President Donald Trump’s agenda.

Questioning the proposal are some of the president’s most hardcore supporters: fiscal conservatives, a small slice of the Hill Republicans who are the most vocal about the exploding national deficit.

Multiple Republican lawmakers told NOTUS that they’re wary of increases in the president’s defense budget unless they’re offset by cuts on the non-defense side. The $1.5 trillion Pentagon budget request for fiscal year 2027 — up from roughly $1 trillion for this year — is divided between more than $1 trillion in regular appropriations and $350 billion in the planned party-line reconciliation process. That’s in addition to a supplemental spending request for military operations against Iran that’s still a question mark.

White House budget chief Russell Vought told lawmakers that officials were “working through that review process” for the supplemental spending request and couldn’t ballpark a cost. “These costs would fluctuate given the day,” he told lawmakers Thursday.

Some of the increase for defense is offset. The budget proposal includes a $73 billion reduction in non-defense discretionary funding — cuts to health research, heating assistance and scores of other domestic programs. The spending plan also carries over $150 billion dedicated to defense from last year’s reconciliation bill.

The budget request does not include deficit and debt projections.

The fiscally hawkish Committee for a Responsible Federal Budget, however, projects it would add $6.9 trillion to the national debt over the next decade. According to the Congressional Budget Office, the annual U.S. budget deficit was projected to hold steady at $1.9 trillion this year, while the national debt reached a record $39 trillion last month.

This week, the International Monetary Fund warned that the world may be headed for a global recession if energy and supply disruptions continue, as the Iran war drives up oil prices and disrupts trade flows. As the fiscal stimulus from the “one big, beautiful bill” wears off, U.S. economic growth is expected to fall to 2% this year from 2.4%, the IMF predicts.

Fiscal hawks are watching those numbers.

“We need to not grow deficits,” Rep. Chip Roy said when asked about the defense request. “So if we have to prioritize defense, then we need to, you know, de-prioritize other things.”Defense Secretary Pete Hegseth and other lead Pentagon officials met with Sens. Mitch McConnell and Chris Coons, the chair and ranking member of the Senate Appropriations Subcommittee on Defense, on Tuesday and their House counterparts, Reps. Ken Calvert and Betty McCollum, on Wednesday. Those lawmakers, who have some concerns of their own, are pressing for weedy budget details that aren’t expected to be made public for at least another week.Last year, the Trump administration divided Pentagon spending between the base budget and reconciliation, pushing a large share of defense money outside of the normal appropriation process. That frustrated Coons and McConnell because it relied on short-term reconciliation funding for long-term defense investments. Now, with another major request taking shape, appropriators are watching for signs that the same dynamic could return.

Vought, for the administration’s part, has said the budget is a “seize-the-moment,” one-shot “paradigm-shifting” investment to expand arms production and strengthen the industrial base for the future.“It’s needed for the Department of War,” he told the Senate Budget Committee on Thursday. “It’s necessary to keep us safe. I’ve never been more confident that the administration is doing what it can to be efficient at the Department of War, but there are bills that need to be paid with regard to drones and munitions and planes.”

Rep. Mike Rogers, the chair of the House Armed Services Committee and a longtime defense hawk, said he will lead the next National Defense Authorization Act to lock in a higher defense baseline, treating the administration’s request as a starting point rather than a ceiling. While that policy bill doesn’t supply appropriations, Rogers said he hopes that it will pass on a bipartisan basis — which would be a marker of what has the broadest political support.

“If you’re increasing spending, are you increasing revenue — if you’re increasing spending in defense, are you cutting somewhere else?” Rep. Warren Davidson, one of two Republicans who voted against Trump’s reconciliation bill last year, told NOTUS. “If you’ve got an idea to spend more money, what’s your pay-for?”

Some fiscal hawks have nuanced views about defense. Rep. Michael Cloud, a senior appropriator and a member of the Delivering on Government Efficiency Subcommittee, said he was open to the request and that offsets for the defense budget should be part of the conversation.

“Defense is certainly our No. 1 priority, constitutionally, to fund in Congress, and so it’s worth the conversation,” he said. “I am concerned about $39 trillion in debt, so we’ve got to figure out how to fund these things as well.”

With last year’s party-line megabill, Republican conservatives and centrists clashed over cuts to Medicaid and clean-energy tax credits. Some in the middle have warned that further safety-net cuts will be painful to find and likely turn off voters ahead of this November’s midterm election.

Democrats already see an opening and are citing the $73 billion package of cuts as reason to oppose the budget request.

“The president is proposing that we cut over $73 billion in our domestic funding for things like education and health care that are critical for our economy, for our families, for the future of our country to help pay for a truly jaw-dropping half-a-trillion-dollar increase in defense spending,” Sen. Patty Murray, the vice chair of the Senate Appropriations Committee, told Vought on Thursday.

Rep. Rosa DeLauro, the House Appropriations Committee’s ranking member, who in 2026 budget talks hammered out a bipartisan deal to derail spending cuts for the National Institutes of Health and the Centers for Disease Control and Prevention, signaled she would hold firm again this time. “We are not going to do that, I just will tell you that right now,” DeLauro said at a hearing into proposed NIH reductions for the next fiscal year.

This week, Davidson acknowledged that fiscal hawks have an uphill fight against fellow Republicans. He recalled how a $9 billion bill that slashed federal funding for the Corporation for Public Broadcasting — eliminating over $1.1 billion for PBS, NPR and local stations — barely squeaked through the House last year. That vote was 216-213.

“It doesn’t really matter what you want to cut,” Davidson said. “There’s usually 70 or so Republicans who don’t want to cut anything.”