"It's money well spent," an energised NATO Secretary-General Mark Rutte told government ministers and defence industry officials on the sidelines of a summit in Turkey on Tuesday.
He was speaking at a defence industry forum billed as NATO's "big reveal", to the thrum of techno music and a slick video display.
Trump, who is slated to arrive in Ankara later on Tuesday, has branded NATO a "paper tiger" that would cease to function without American arms and leadership.
NATO as an organisation does not own any weapons - these are the property of the 32 member countries - but it does have a fleet of 14 AWACS early-warning radar surveillance planes that are about 50 years old, along with some newer surveillance drones.
A deal to replace the ageing planes was announced on Tuesday, with Swedish manufacturer Saab supplying up to 10 new GlobalEye surveillance aircraft for a 10-nation consortium.
"It's a moment of great pride," Swedish Prime Minister Ulf Kristersson announced, noting the twin-engine aircraft would be "made within the alliance for all the alliance".
Representatives from 15 nations shook hands and patted shoulders on a vast podium under the NATO logo as they announced a multinational effort to buy air-to-air refuelling and transport planes from Airbus.
Then Rutte announced a four-country effort to purchase as many as five new Triton surveillance drones to add to NATO's small fleet.
"It is genuinely made in NATO, and creating jobs on both sides of the Atlantic," he said.
Rutte told reporters on the eve of the military alliance's two-day summit in Turkey that "we will announce tens of billions in new contracts that will provide the crucial kit we need to deter and defend".
However, at Tuesday's event, no dollar figures were given and the display included some projects long since agreed.
The defence industry splash comes a few weeks after Rutte tried to ease US concerns about military spending at NATO with a new pitch using a chart labelled the "The Trump Trillion" - showing $US1.2 trillion ($A1.7 trillion) in spending by European allies and Canada since 2017.
Far from being impressed, Trump appeared unmoved, saying he was still disappointed at some NATO allies' refusal to join the Iran war, which he had launched alongside Israel without consulting them.
"We don't need their money - we don't need anything," Trump said. "I just want loyalty."
The summit is being held in President Recep Tayyip Erdogan's sprawling palace compound in Ankara, where the meeting's focus is a stronger Europe for a stronger NATO.
The Trump administration has warned the allies that they must handle Europe's security alone as the United States focuses on China and the Indo-Pacific region.
But hiking defence spending means increasing taxes or diverting resources from other priorities.
UK Defence Secretary John Healey unexpectedly quit in June, saying the British government was not willing to spend at a time of rising threats.
Concern is mounting among some northern and central eastern countries that Russia might be preparing a hybrid attack - a combination of conventional warfare with tactics such as cyberattacks - on the continent as Russian President Vladimir Putin struggles to secure victory in Ukraine.
Keir Starmer's office said the British leader will be "focused on building a stronger and more European NATO" on what is likely to be his last foreign trip as prime minister following his resignation on June 22.
Starmer has faced criticism for the slow rate of increase in UK military spending, though his government has committed to reach the NATO budget target of spending 3.5 per cent of gross domestic product on defence by 2035.
