The Pentagon has ordered the U.S. defense industry to ramp up production to quickly replenish weapon stockpiles depleted by the ongoing war with Iran.

Specifically, defense contractors have been told to accelerate the production of critical weapons and ammunition and speed up supply timelines to replace items consumed during the conflict.

U.S. Deputy Secretary of Defense Steve Feinberg issued these directives in a letter, according to reports.

Al Jazeera reports that Washington-based think tank CSIS has stated that the inventory of crucial missile defense systems has already dropped significantly compared to pre-war levels.

In a statement last Saturday, Pentagon spokesperson Sean Parnell said the Department of Defense is actively working to accelerate the procurement of weapons and ammunition to quickly supply troops with necessary armaments based on threat levels. He noted that initiatives to significantly speed up this process have been undertaken over the past week.

U.S. Faces Missile Defense Shortages, Concerns Arise Over Surviving Iran War

However, he claimed that this is not merely a step taken due to the past five months of conflict, but part of a broader, pre-existing military modernization program.

According to Al Jazeera, U.S. Deputy Secretary of Defense Steve Feinberg sent a letter to top defense industry executives last Wednesday.

Obtained by The Washington Post, the letter states that relevant companies must submit plans within a maximum of 21 days to increase the production of critical military capabilities and significantly reduce delivery times.

Feinberg wrote, "Years-long development processes are no longer acceptable. We must immediately and drastically compress our program timelines and scale up production capacity."

In the recent fighting with Iran, the U.S. has seen its already depleted stockpiles of advanced missile defense systems shrink further. Experts warn that shortages in both offensive and defensive weapons could put American troops at risk.

Meanwhile, an analysis by the Washington-based Center for Strategic and International Studies (CSIS) indicates that dwindling stockpiles of Patriot and Terminal High Altitude Area Defense (THAAD) missile defense systems may force the U.S. and its allies in the Middle East to be more conservative in utilizing these defensive systems.

As an example, the analysis suggests that U.S. forces might fire fewer defensive missiles to intercept incoming Iranian drones and missiles, increasing the risk that some Iranian projectiles could pierce the defense and strike targets.

On the other hand, U.S. President Donald Trump was angered by the exposure of reports regarding the declining weapon stockpiles.

Last Thursday, he maintained that the U.S. has not fallen into any strategic disadvantage regarding its weapons inventory despite five months of war.

Writing on his Truth Social account, Trump stated, "The United States has a massive amount of weapons and ammunition, especially certain types." He further claimed that massive quantities of weapons are being produced and shipped to the U.S. as needed, and that defense companies are building more factories and production facilities than ever before in the nation's history.

On Saturday, Pentagon spokesperson Sean Parnell confirmed the authenticity of Feinberg's directive to rapidly increase weapon production. He stated that it will be factored into the formulation of the fiscal year 2028 budget and is fully aligned with ongoing initiatives to rebuild the capacity of the U.S. defense industry.

Meanwhile, a defense spending bill remains stalled in the U.S. Congress, with lawmakers expressing anger over Trump's military campaign against Iran.

At the same time, they are opposing the White House's request to increase the Pentagon budget from nearly $900 billion last year to $1.5 trillion.

Experts have warned that even with additional funding, it could take at least three years to restore Patriot and THAAD missile defense stockpiles to pre-war levels.

According to CSIS estimates from last month, the U.S. had 2,330 Patriot interceptor missiles before the war began. By the time a ceasefire took effect in April, that number had dropped to 1,030.

Following the recent fighting, stockpiles are estimated to have fallen further to between 759 and 827—representing at least a 65% decline compared to pre-war levels.

The number of THAAD interceptor missiles stood at 452 before the war. When the April ceasefire began, that figure dropped to between 232 and 262, according to CSIS.

The U.S. subsequently managed to stockpile some missiles, raising the count to between 234 and 278. However, inventory remains at least 38% lower than pre-war levels.

Earlier this month, the U.S. Department of Defense signed new contracts with major defense contractors Lockheed Martin and Northrop Grumman to boost the production of various components used in missile defense systems.

Mark Cancian, a senior analyst at CSIS and a retired U.S. Marine Corps colonel, told Al Jazeera last Wednesday, "We don't have very many interceptors, and we don't have good substitutes. Once the Patriots are gone, the missiles are going to get through."