Ukrainian soldiers are rationing ammunition as a hold-up in the US approving a military aid package is affecting how it conducts its war with Russia, western officials said on Thursday.
Ukraine has made recent military gains on Russia in the Black Sea, including the sinking of a Russian missile ship this month.
But soldiers on the battlefield are running low on certain types of ammunition and air defence, piling additional pressure on Ukraine's western allies to step up defence production.
"We really need to step up our game," said Dutch Defence Minister Kajsa Ollongren at a meeting of her Nato counterparts in Brussels.
"We are very much committed to giving the ammunition that Ukraine needs and providing them with that but we are struggling, of course, on the side of our production capacity," Ms Ollongren said.
Concern has been mounting in EU capitals over Europe's inability to keep up with Ukrainian needs.
The EU's foreign policy and security chief Josep Borrell has suggested countries start selling weapons only to Ukraine and not elsewhere.
Ukraine defence industry under attack
Speaking anonymously, a western official said battlefield commanders in Ukraine were "quite concerned".
"We know that some of those units are marshalling their ammunition quite closely, they’re deciding how many munitions they’re going to fire on any given day," they said.
"It’s worth noting that from an air defence standpoint, most notably medium to long-range defence, Ukraine is expending those air defence assets at a rate they’re quite concerned about."
Russia has understood this concern which is why it has stepped up strikes on Ukraine's defence industrial base, the source added.
"It’s important that support coming from Nato allies and from others to Ukraine to continue," they said.
Further compounding worries over Ukraine, a massive US aid package has become bogged down by local politics.
The US Senate on Tuesday approved a $95 billion package for Ukraine, Israel and Taiwan by a comfortable margin but House Speaker Mike Johnson, a Donald Trump ally, has refused to put it to a vote in the lower chamber.
"These plans will improve our ability to deter and defend against any threat, well into the future", US Defence Secretary Lloyd Austin said, adding that "US leadership on the world stage will not diminish".
Mr Austin said that Western allies also must continue to invest in their defence industrial bases, which he said "is crucial to the future strength of the alliance".
The delay on support has had a considerable effect, Nato Secretary General Jens Stoltenberg said.
"I expect the US to be able to make a decision, that Congress and the House of Representatives will agree continued support to Ukraine,” he said.
Mr Stoltenberg has sharply criticised Mr Trump for claiming he would not defend Nato members that do not meet defence spending targets should he be elected US president this year.
Mr Stoltenberg said US criticism is not "primarily aimed at Nato".
"It's against Nato allies not spending enough money on Nato," he said, referring to a recent increase in spending.
"Things have really changed. I expect 18 allies to spend 2 per cent of their GDP on defence this year, a six-fold increase from only three allies in 2014."
He also warned member countries against allowing the issue to drive a wedge between the United States and Europe.
“I welcome that the European allies are investing more in defence, and Nato has called for that for many, many years,” Mr Stoltenberg said.
“But that’s not an alternative to Nato. That is actually a way to strength Nato. And we should not pursue any path that indicates that we are trying to divide Europe from North America,” he said.
Hungary still blocking Swedish accession
UK Defence Secretary Grant Shapps said it was “simply unconscionable” to think Ukraine might lose the war. “We need to make sure that civilised nations are prepared to stand right behind Ukraine,” he said.
Mr Shapps also announced the UK, in partnership with Latvia, would send thousands more drones to Ukraine. This is the first project to be launched from a £200 million ($251 million) package announced by Prime Minister Rishi Sunak last month.
Western officials have also expressed frustration with Hungary for being the last country to block Sweden's accession to the alliance, following Turkey's approval in January after a 20-month delay.
Officials perceive the blockage as Hungary's Defence Minister Kristof Szalay-Bobrovniczky breaking a promise made to his Nato counterparts that his country would not be the last to give approval.
“Sweden must join Nato now,” German Defence Minister Boris Pistorius said. “Any further delay is straining everyone's patience.”
Hungary has not clarified its objections to Sweden's membership. The only criteria for a country to join Nato is that it enriches the alliance's security.
But several defence ministers struck an optimistic tone after Thursday's meeting.
"I had a good and constructive dialogue today with my colleague from Hungary," Sweden's Pal Jonson told The National.
"Hopefully the Hungarian Parliament will make a decision as soon as possible."
Ms Ollongren said: "It was pretty clear today that every country around the table said the time has come for Sweden to finally enter as a fully fledged member.
"As I have understood, Hungary suggested it is also from their side – they are taking the right steps to have a decision in Parliament as soon as possible."
Nato through the years – in pictures
