Europe Made a Bold Pledge of Ammunition for Ukraine. Now Comes the Hard Part.

The pledge last March sounded as catchy as it was ambitious: European Union states would deliver a million rounds of 155-millimeter ammunition to Ukraine within a year.

Now, at a critical moment in the war and with Ukraine running short of artillery shells to drive its counteroffensive, experts, weapons manufacturers and even some government officials are expressing growing doubts. Europe’s shrunken military sector, they say, may simply be unable to ramp up production fast enough to achieve the million-shell goal.

Since March, governments across Europe have become more aggressive about assessing — and replenishing — ammunition needs, not just for Ukraine, but also for their own military stockpiles.

Manufacturers are building 155-millimeter rounds even before being fully paid. And European Union officials have fast-tracked at least eight contracts with producers on the continent to supply and reimburse states that jointly procure artillery ammunition instead of competing for it.

But for all of the efforts to increase supplies since the European Union announced its goals, weapons makers are running into a familiar problem: After atrophying badly in the 30 years since the end of the Cold War, they still have too few resources and too many supply chain bottlenecks to deliver the one million rounds by the deadline.

“I don’t know where these rounds are coming from,” said Morten Brandtzaeg, the chief executive of Norway-based Nammo, which produces about 25 percent of Europe’s ammunition. “The industry capacity is not there.”

“I think we should not say that it’s not doable,” he added. “But I cannot see quite how right now.”

Peter Stano, a spokesman for the European Union, maintained that the bloc was doing what it could. “The intention of the E.U. is clear: to help,” he said in an email. “This is what everyone involved is trying to do with best intentions.”

Last March, as Ukrainian soldiers were burning through thousands of artillery shells each day just to retain control of the eastern city of Bakhmut, the government in Kyiv sent a dire plea to its allies for more 155-millimeter ammunition, which is fired from the howitzers that are the backbone of Ukraine’s military.

Within weeks, the European Union agreed to a $2.1 billion plan to send Ukraine the one million rounds, drawing on donations from member states’ stockpiles and ammunition purchases. It is also seeking to increase production at aging plants across Europe, with up to $532 million in financing through mid-2025.

In August, the most recent available numbers showed that the European Union states and Norway had sent Ukraine at least 223,800 artillery shells from February to May — about one-quarter of the goal. Most of the munitions came from military stockpiles, for which they were reimbursed $1.1 billion.

But that was the relatively easy part, given that they came from ready supplies. Now those stocks have run too low for most militaries to give more, experts said.

Under the terms of the program, many of the remaining rounds must be bought from manufacturers based in the European Union and Norway, and purchased in joint procurement deals among those states in order to qualify for reimbursement.

In theory, experts said, European Union states could buy ammunition from beyond the bloc, including from Britain, the United States and South Korea — three major global producers and exporters of 155-millimeter rounds. But that defies the point of a program aimed to bulk up European manufacturing and would forfeit financial incentives from a $1 billion fund for the joint purchases.

Moreover, South Korea has prohibited its weapons from being sent to Ukraine, and Britain and the United States are trying to rebuild their own stockpiles as NATO urges its members to bolster depleted reserves as a safeguard.

“Stockpiles serve as a deterrent against potential aggression,” Erika Kurockina, Lithuania’s deputy economy and innovation minister, said in a speech in London this month.

The Pentagon has said that American manufacturers expect to produce 57,000 rounds of 155-millimeter shells a month by next spring. Even if all of that were sold to European Union countries and then sent to Ukraine, it alone still would not close the gap.

Before the war in Ukraine, some officials and experts estimated that European manufacturers produced 230,000 rounds of 155-millimeter ammunition annually. (Experts have put the number for all types of rounds produced in the European Union at about 650,000 a year.)

The output is expected to be higher this year — even if it falls short of fulfilling the goal of sending one million rounds to Ukraine.

“It will be close,” Dominique Guillet, an executive vice president of the French ammunition firm Nexter Systems, said last week in London.

Whether or not European Union states are able to meet the March 2024 deadline, it is clear that the ambitious plan prodded governments and the arms industry into action.

Just since March, Mr. Brandtzaeg said, Nammo has received about $1 billion worth of artillery orders, compared with an estimated $300,000 in contracts the company would usually sign over a six-month period.

Rheinmetall, the German defense industry giant, has predicted that it will be able to produce 600,000 artillery shells annually by the end of 2024, up from the 450,000 it expects to turn out this year. It has landed several major ammunition contracts this year — including one worth nearly $1.4 billion to supply Germany’s military — and has produced tens of thousands of rounds that have been sent to Ukraine since the war began.

This month, Germany announced that it had shipped to Ukraine a first tranche of a contract for 300,000 rounds of other kinds of ammunition — mostly for tanks that shoot down drones and other aircraft — that it had ordered from Rheinmetall in February. The quick turnaround demonstrated how nimbly government and industry could cooperate when pressured.

But most of the newly awarded contracts will not be fulfilled until the end of the decade, and industry officials declined to specify how much of the ammunition could be produced in time to be delivered to Ukraine to meet the one-year deadline.

“We’re all doing our utmost to achieve this goal,” said Oliver Hoffmann, a spokesman for Rheinmetall. He was one of several industry executives who said more long-term contracts for ammunition were needed not only to pay for manufacturing upgrades and raw materials that were in global demand, but also to ensure that production would continue once war demands ebbed.

Despite the daunting odds of making the deadline, European officials are still scrambling to find other ways to scrape together the one million rounds.

Kusti Salm, the highest-ranking career official at Estonia’s Defense Ministry, who helped conceive the plan that the European Union eventually adopted, said Europe could not depend on industry alone to make up the nearly 750,000-round shortfall that it faced.

“If you were able to supply 200,000 a year before, then it’s fair you cannot trigger turning to one million a year,” Mr. Salm said in an interview last month.

He said states and manufacturers were asking countries outside the European Union to delay deliveries of 155-millimeter shells in return for a discounted price, freeing up ammunition for Ukraine.

The refurbishment of older or otherwise decommissioned stocks of 155-millimeter rounds in military stockpiles offers another possible source. But Mr. Brandtzaeg estimated that they accounted for fewer than 10,000 rounds, a small fraction of what is needed.

And though the initial European focus was on 155-millimeter artillery shells, officials said in May that the one million for Ukraine could include ammunition of other sizes, including Soviet-era caliber munitions, depending on what was needed on the battlefield.

Smaller countries are also pitching in. Industry officials said the Turkish government-owned firm MKEK had signed a two-year contract this year with Romania to build 155-millimeter shells. Bulgaria’s defense minister has predicted that his government will supply some of the ammunition for Ukraine. In Greece, the European Union has committed up to $80 million to upgrade an ammunition plant owned by Hellenic Defense Systems.

“There’s a risk that we don’t hit the milestone, but in the long term I think the steps are being made in the right direction,” Mr. Salm said. He said setting the one million goal “was ambitious yet achievable” and necessary to prod European Union states and the weapons industry into ramping up production.

Still, he said, “clearly it’s too slow for winning the war in Ukraine.”

Juliette Guéron-Gabrielle contributed reporting from Paris.