Defense Secretary Pete Hegseth and Joint Chiefs Chairman Gen. Dan Caine are appearing Tuesday before the House and Senate subcommittees that oversee Pentagon budget requests as the Trump administration is seeking $1.5 trillion amid the Iran war. 

Hegseth and Caine will appear in back-to-back hearings before the House and Senate Appropriations subcommittees that oversee defense spending. The $1.5 trillion fiscal year 2027 budget proposal, which serves as a starting point for negotiations with Congress over annual spending, would mark a 42% increase in defense spending from 2026 levels.

President Trump said Monday that the ceasefire with Iran is "on life support" after he called the latest Iran peace proposal "totally unacceptable." Mr. Trump told CBS News that he aims to suspend the gas tax amid soaring gas prices. 

Democratic Sen. Mark Kelly of Arizona, who is on the Senate Appropriations Committee, called the $1.5 trillion number "outrageous." 

"When I got to the Senate five and a half years ago, the defense budget was just over $700 billion," Kelly said Sunday on "Face the Nation with Margaret Brennan." "Now they're asking for twice as much money — it's nearly the amount that the rest of the world pays for its defense."

The hearings are also coming as the Trump administration has faced increasing backlash for not getting the Iran war approved by Congress. While several war powers resolutions have failed to advance, two Republicans – Sens. Susan Collins of Maine and Rand Paul of Kentucky — have joined Democrats in favor of advancing the measure to limit Mr. Trump's war powers. And GOP Sen. Lisa Murkowski of Alaska has said she intends to introduce a formal authorization for the use of military force in Iran. 

Hegseth testified last month before the House and Senate Armed Services Committees that the conflict has cost $25 billion so far, but U.S. officials familiar with internal assessments suggested at the time that the Iran war's price tag could be closer to $50 billion.