Nato Secretary General Jens Stoltenberg on Monday said the alliance was planning to increase its targets for ammunition stockpiles.
The war in Ukraine is increasing pressure on Europe's defence industry, with the waiting time for weapons deliveries stretching to several years.
“The current rate of Ukraine’s ammunition expenditure is many times higher than our current rate of production," Mr Stoltenberg said before a two-day meeting of Nato defence ministers in Brussels.
"This puts our defence industries under strain.
"For example, the waiting time for large-calibre ammunition has increased from 12 to 28 months. Orders placed today would only be delivered two-and-a-half years later."
Nato has completed an “extraordinary survey” of its ammunition stockpile, said Mr Stoltenberg, who also praised recent defence contracts signed by Nato members France and the US.
“We are on the right track, with eight consecutive years of increases by European allies and Canada, and an additional $350 billion extra spent so far,” he said.
Also high on the agenda at this week's meetings will be the protection of Nato's critical infrastructure, five months after the Nord Stream gas pipelines were damaged in mysterious blasts.
Sweden and Denmark, in whose exclusive economic zones the explosions occurred, have concluded the pipelines were blown up deliberately, but have not said who might be responsible.
Nato has called the incident “an act of sabotage”. Russia on Saturday called on the alliance to hold an emergency meeting to discuss the findings of investigative journalist Seymour Hersh.
Quoting an unidentified source, Mr Hersh wrote in a blog post last week that US Navy divers were behind the attack.
The White House has dismissed the claim as “utterly false and complete fiction”.
Mr Stoltenberg said Nato had established a new co-ordination cell to map out vulnerabilities of its critical infrastructure to prevent and counter threats to undersea cables and pipelines.
Allies would establish a virtual network of national and commercial satellites, he said, and discuss transferring fighter jets to Ukraine to assist its war effort against Russia.
He repeatedly said that making new weapons pledges was not as important as finalising what had already been promised.
“Whatever the opinion is about aircraft, that will take time,” Mr Stoltenberg said.
“What is needed now is urgent support for Ukraine. So my top priority is to ensure that pledges allies made for infantry fighting vehicles, for armour, for battle tanks — that they are delivered as soon as possible because every day counts.”
He also backed reports from Ukrainian officials that a major new Russian offensive had begun in Bakhmut.
Bakhmut is a prime objective for Russian President Vladimir Putin, and its capture would give Russia a new foothold in the Donetsk region and a rare victory after months of setbacks.
The Donetsk and Luhansk regions make up the Donbas, Ukraine's industrial heartland, now partially occupied by Russia, which wants full control.
"We see how they are sending more troops, more weapons, more capabilities," Mr Stoltenberg said, adding that it was the start of a new offensive.
He also said Nato would be sending shelters to Turkey, which along with Syria was last week hit by an earthquake that has so far claimed the lives of at least 35,000 people.
Nato also provided transport after the earthquake.
“It is important that we get support quickly but also that we are able to stay because this earthquake will have consequences for a long time,” Mr Stoltenberg said.