European allies are looking on in disbelief and growing concern as the US appropriates weapons they've paid for use in the Operation Epic Fury that started on February 28.

In the midst of the ReArm (video) Defence modernization program and on the hook to supply Ukraine through the Prioritised Ukraine Requirements List (PURL) program, the depleted European military is desperate for fresh supplies of US-made weapons.

Ukrainian President Volodymyr Zelenskiy is even more desperate. After surviving a winter campaign to freeze Ukraine into submission, the Armed Forces of Ukraine (AFU) is scraping the bottom of the barrel of the Patriot systems PAC-3 interceptor missiles a shortage of which has left Ukraine’s skies open. Last week Zelenskiy offered to swap its drone interceptor systems for Patriot ammo as the Middle East is well supplied with PAC-3 ammo, but the sophisticated and expensive systems are in effective against Iran’s swarms of drones that give it a large cost-to-kill ratio advantage in any sustained conflict.

The US has also depleted its stockpile of Patriot ammo and is now increasingly drawing on supplies in other theatres. As both the US and Europe were reluctant to sign off on the defence sector procurement contracts during the four-years of war in Ukraine, the defence sectors in both are unable to ramp up production now a fresh large-scale war has broken out.

European allies are increasingly concerned that the US military campaign against Iran is consuming munitions at a pace that could delay or disrupt deliveries of American weapons they have already purchased. The US reportedly burnt through five-years worth of Tomahawk missiles in just the first four days of the Iranian conflict and has already scaled back its volleys in an effort to preserve ammo. US President Donald Trump reportedly called the CEOs of the major arms producers into the White House last week and demanded they massively ramp up production, but was told it will be at least a year before production can accelerate due to the need for time-consuming investments.

Officials from nearly a dozen EU governments told Politico that the Pentagon’s decision to reroute weapons shipments to support operations in the Middle East has left partners concerned  that systems the White House demanded they during the Nato summit in the Hague may not arrive on schedule.

“It shouldn’t be a secret to anyone that the munitions that have been and will be fired are the ones that everybody needs to acquire in large numbers,” one northern European official told Politico.

Many European governments are also scrapping the bottom of the barrel as well by supplying Ukraine since Russia’s full-scale invasion in 2022. They fear that delays in US deliveries could weaken their ability to deter Moscow just as peace talks move into a final round following a Moscow meeting on December 3 that agreed on an outline 27-point peace plan (27PPP).

Asian allies have expressed similar concerns after Washington proposed to transfer the air defence THAAD systems from US bases in Asian to the Middle East and undermine military readiness in the Indo-Pacific, where China and North Korea remain major security threats.

“It is very frustrating, the words are not matching the deeds,” said an Eastern European official. “It is pretty clear to everyone that the US will put their own, Taiwan’s, Israel’s, and hemisphere priorities before Europe.”

Pentagon officials have privately warned that the US military is expending “an enormous amount” of munitions in the war, and Secretary of War Pete Hegseth admitted over the weekend that the Pentagon had underestimated the effectiveness of Iran’s drones, which bne IntelliNews military analyst Patricia Marins described as “cheap cruise missiles.”

A congressional aide told Politico, the US was using precision strike missiles and advanced air defence interceptors in “scary high” numbers, including Tomahawk land-attack missiles, Patriot PAC-3 interceptors and ship-launched air defence systems fired by the US Navy.

The EU was already struggling to up its production and has descended into a petty fight over spending. Following the approval of the €90bn EU loan in December, of which two thirds will be dedicated to defence spending, French President Emmanuel Macron has blocked the distribution of the loan, saying the money should be spent on European-made arms, not of the purchase of US-made munitions. Furthermore, the loan is currently tied up by a Hungarian veto, in retaliation for being cut off from supplies of Russian gas via the Druzhba pipeline that was damaged by a drone strike in January.

In Washington, some lawmakers have also raised alarm about stockpiles. Senate Minority Leader Mitch McConnell warned that the US military is “not prepared” to deter Russia and China simultaneously because of shortages in key munitions, Politico reports.

Trump has dismissed the concerns of over the shortage of munitions, saying the US as “unlimited” supplies.

Nato Secretary General Mark Rutte, speaking in the Verkhovna Rada last month, said that since last summer, 75% of all front-line missiles and 90% of air defence missiles have been delivered to Ukraine via the PURL mechanism for the procurement of American weapons.

"We understand deliveries should be even faster, and we are constantly working to ensure that resources arrive through both PURL and other channels", Rutte told the deputies.

This year, an addition $15bn of spending on US arms was planned as part of Bankova’s war strategy through the PURL initiative.

In February, the following countries have already contributed: $500mn jointly from the UK, the Netherlands, Norway, and Sweden; $100mn from Estonia, Iceland, Latvia, and other allies. Last year, partners nearly fully funded ten military assistance packages totalling about $4.3bn.

Kiel Institute data shows that just six countries — Germany, UK, Norway, Sweden, Denmark, Netherlands — account for the bulk of Europe's military aid to Ukraine. Scandinavia alone accounts for just 8% of Europe's GDP, but has supplied a third (33%) of this weapons funding.

However, despite a significant uptick in European defence spending in 2025, Europe has not managed to offset the fall in US support since Trump took office and halted all direct supplies of munitions and money and both weapons supplies fell last year as a result.