The two-month war with Iran has cost about US$25 billion, a Pentagon official told lawmakers on Wednesday, as US Defence Secretary Pete Hegseth defended a record $1.5 trillion military budget that faces backlash from Democrats.

At a House Armed Services Committee hearing on Wednesday, Jules Hurst III, the Pentagon’s chief financial officer, offered the first official estimate of the cost of the war in Iran.

He said that most of the US$25 billion in spending went towards ammunition, but the US military also allocated funds for operations and equipment upgrades.

Hurst was one of the witnesses at the hearing on the Pentagon’s record-breaking budget. Seated next to him were defence secretary Hegseth and General Dan Caine, chairman of the Joint Chiefs of Staff.

In a packed hearing room, Hegseth faced his first congressional questioning regarding the war on Iran since the US and Israel launched strikes against Iran on February 28.

The top defence official, a former Fox News host who has been the subject of considerable controversy, began his remarks by apparently taking aim at Congress: “The biggest challenge, the biggest adversary we face at this point are the reckless, feckless and defeatist words of congressional Democrats and some Republicans.”