The United States Department of Defence has confirmed that its military campaign against Iran has resulted in shortages of some munitions, according to a report by the department’s Office of Inspector General.

The report, submitted to Congress, said the expenditure of weapons during Operation Epic Fury had created strategic inventory shortfalls and exposed limitations in the defence industry’s ability to replenish stocks.

Between February 28 and June 30, the operation was estimated to have cost $33.4 billion, including $22.3 billion spent on munitions.

The report said the Pentagon was working to speed up procurement and production timelines while building stockpiles of critical materials, components and selected weapons.

It noted, however, that expanding production capacity would require significant lead time.

The shortages could create difficulties for countries that depend on US weapons to defend themselves or deter potential adversaries, including Ukraine and Taiwan.

Ukraine requires additional interceptor missiles for its US-made Patriot air-defence systems in its war against Russia, while Taiwan relies on US arms agreements as part of its defence strategy against China.

The report's findings contrast with President Donald Trump’s repeated assurances that the US has sufficient weapons. Trump recently described the country as having “virtually unlimited” ammunition and said US production of advanced weapons was at an all-time high.

The Inspector General’s report also detailed military losses during the conflict, including four F-15 fighter aircraft destroyed, one F-35 damaged, seven KC-135 tanker aircraft damaged and up to 30 MQ-9 Reaper drones destroyed.

It said Iranian drone and ballistic missile attacks had also damaged or destroyed hundreds of buildings and structures at US bases across Bahrain, Kuwait, Qatar, the United Arab Emirates, Saudi Arabia, Iraq, Oman and Jordan.

As of June 30, seven US service members had been killed in action and another seven in non-hostile incidents during the operation, while 417 were wounded in action.