US Defense Secretary Pete Hegseth has told lawmakers that the United States' war in Iran has cost $37.5 billion so far, an increase of nearly $8 billion since the last public estimate.
Hegseth told the Senate Appropriations Committee that the figure also included anticipated costs through 30 September.
Hegseth, who appeared alongside Chairman of the Joint Chiefs of Staff General Dan Caine, faced questions and protests over the war as Republicans prepare a $95 billion budget package to fund the military and White House priorities.
Protesters interrupted Hegseth's opening remarks, which came days after the Pentagon announced that three more American service members have died, bringing the death toll to 17.
Hegseth called the funding an "urgent, necessary" injection of money.
"Without these funds, we face critical shortfalls," Hegseth testified.
Democratic warnings
Senator Patty Murray, the top Democrat on the panel, warned of "another forever war".
"This war is now spiralling out of control again," Murray said, noting President Donald Trump is asking for tens of billions more.
War funding makes up the bulk of the proposal ahead of the midterm elections.
"The commander in chief and the whole Department of War are working very hard to bring this to a resolution," said House Speaker Mike Johnson.
Hegseth appeared facing questions about the war and his leadership.
Senator Susan Collins said it is "deeply troubling" that the Pentagon has blocked or denied promotions to various officers, particularly women and minorities.
Senate Democratic Leader Chuck Schumer criticised Hegseth regarding casualty disclosures.
Nearly 450 service members have been injured since the start of the war.
Senators have also pressed Hegseth to release the report on an Iranian primary school attack.
