A US Department of Defense oversight body has acknowledged ammunition shortages resulting from the Iran war, in a first official report to Congress.

Ammunition consumption during “Operation Epic Fury” caused “strategic inventory shortfalls” and “revealed industrial base bottlenecks for munitions resupply,” said the report, which was released on Monday.

To reduce these shortages, the Department of Defense said it was working to streamline procurement processes and production lead times and to stockpile critical materials, components and selected munitions “to respond rapidly to a contingency,” The report was produced by the Pentagon’s inspector general, an independent body within the department. It covers the period from April 1 to June 30.

According to the report, the Department of Defense estimates the cost of the mission up to the end of June at $33.4 billion. Expended munitions account for over $22 billion, making it by far the largest item of expenditure.

US ammunition stocks have been a politically sensitive issue since the war began at the end of February.

Secretary of Defense Pete Hegseth had repeatedly rejected reports of ammunition shortages. US President Donald Trump has also pushed back against such reports, threatening those who spread them with lengthy prison sentences.

On Monday, Trump wrote on his Truth Social platform that the US was producing “more Exquisite and Elite Weapons than at any time in our History.”

These were being delivered daily to US forces in the Middle East and beyond, he added.