Getting there though is going to be a tough slog.

After decades of depending on the United States for its security, officials on both sides of the Atlantic say Europe should no longer be so reliant on Washington.

"We want Europe to be strong," US Secretary of State Marco Rubio told the Munich Security Conference on Saturday.

That message appeared to chime with those delivered by leaders including German Chancellor Friedrich Merz and French President Emmanuel Macron.

"Europe needs to step up and has to take on its responsibility," said EU chief Ursula von der Leyen.

Beneath the surface the reasoning was different.

Washington argues allies have to stop taking advantage of US largesse and take over Europe's conventional defences so it can focus on other threats like China.

But for European leaders, worries over US President Donald Trump have driven the latest sense of urgency.

As the continent grapples with the menace of Russia four years into the Ukraine war, Trump rocked NATO by making claims on Greenland.

That plunged the alliance into its deepest crisis in years and compounded the sense that the United States cannot be counted on.

Last year, under pressure from the mercurial US leader, allies already promised to ramp up their defence budgets over the next decade.

But making the pledges is just the first step -- now Europe has to turn them into the cash, weapons and troops to defend itself.

"It's not going to be easy. It's not going to be cheap," said US ambassador to NATO Matthew Whitaker.

"We're in for a decade of really hard work."

- 'Shift of mindset' -

NATO chief Mark Rutte insisted that there had been a "real shift in mindset" among European members of the alliance.

Military expenditure has risen since Russia invaded Ukraine in 2022 -- with economic powerhouse Germany making notable strides.

But Rutte said his priorities were to maintain pressure for all of Europe to make good on its spending pledge and to ensure industry was able to produce all the weaponry needed.

"We have to keep total focus on this," Rutte told journalists.

The defence minister of Estonia Hanno Pevkur -- whose country has taken a lead on defence spending in the face of neighbouring Russia -- agreed.

"We have the challenge still to increase defence budgets in many, many countries," Pevkur told AFP.

"We have the challenge how the industry can cope with that money."

Finding the troops to fill the ranks was also a concern.

"For the countries who don't have conscription, there is definitely a debate, should we have a conscription? Should we build up reserves?," he said.

As worries swirl over the US reliability on one side and the menace from Russia on the other -- some warned that even hitting NATO's new targets might prove insufficient.

Danish Prime Minister Mette Frederiksen said her country already reaches NATO's requirement of 3.5 percent of GDP on defence.

She said others needed to step up well before the deadline set of 2035 -- and even then more could be needed.

"I'm not sure it will be enough," she said.