The United States incurred billions of dollars in costs during the first 100 hours of its war against Iran, according to a report by the Washington-based think tank Centre for Strategic and International Studies.

The report estimates that the initial phase of the conflict cost Washington about $3.7 billion, covering military operations, weapons deployment and defence systems.

In Pakistani currency, the amount equals roughly Rs1.028 trillion, nearly half of Pakistan’s annual defence budget of around Rs2.1 trillion, spent by the United States in just four days.

According to the analysis, the war is currently costing the US an average of $891.4 million per day, equivalent to approximately Rs247.8 billion daily.

The report said the early stages of the campaign against Iran involved extensive air and ground operations, requiring the use of advanced weapon systems that significantly increased operational costs.

However, analysts noted that the US military could gradually shift toward lower-cost weapons and systems, which may reduce expenses over time.

The report warned that if the conflict continues for several weeks, the United States Department of Defence may require additional funding because the current budget does not fully account for the total costs of the war.

The think tank also noted that financing the war through budget cuts elsewhere could prove politically and practically difficult.

Both Donald Trump and Pete Hegseth have indicated that the conflict with Iran could last for several weeks, raising expectations of further increases in military expenditure.

Experts estimate that if the war continues at its current intensity, total US military spending could reach between $40 billion and $95 billion.