Promises of increased defence expenditure rose from member states following Russia’s invasion of Ukraine, amid growing fears the war could spill over into Europe.
It ushered in an “unprecedented rise of 11 per cent”, Nato’s secretary general said.
In 2014, when the spending target was set at a summit in Cardiff, just three countries reached the goal – Britain, the US and Greece.
Watching the race for the White House
After Mr Trump’s outburst at a campaign rally on Feb 10, Nato diplomats acknowledged the only way to ensure his support if he wins the presidency for a second time is to continue to increase spending.
The former US president has previously threatened to withdraw America from the alliance if its European members don’t do more to protect themselves.
If he wins the White House race, the alliance will increase its focus on the threats posed by China and terrorism to manage his opposition, one source said.
Dutch prime minister Mark Rutte, who will retire from domestic office when a new government is formed, is seen as a crucial part of managing Mr Trump’s potential return to power.
Britain, Germany and the US have privately voiced their backing for Mr Rutte to become the next secretary general of Nato, sources told the Telegraph.
Internally, only Hungary and Turkey are seen as potential opponents, but don’t pose an insurmountable challenge, the insiders added.
Mr Rutte is seen as experienced enough on the world stage, having held office in the Netherlands for more than a decade.
The alliance had previously expressed a desire to recruit a female secretary general, but it is now believed a man has a better chance standing up against what is perceived as Mr Trump’s misogyny.
The Netherlands also uses a host of US-developed weapon systems, including the F-35 fighter jet and Patriot air-defence missile system, which will maintain the transatlantic bond.
Mr Rutte is also seen as the strongest candidate, given his reluctance to match French President Emmanuel Macron’s calls for a more autonomous European Union defence infrastructure, which relies less on Nato and Washington.