Donald Trump’s ambassador to Nato has given the clearest indication yet that the US president will be attending the defence alliance’s summit in The Hague next month.

“I expect and plan, and we should fully expect that Donald Trump will be in The Hague for the Nato summit,” Matthew Whitaker, who has been the United States permanent representative to Nato, told a press briefing on Tuesday.

“We’re all planning on President Trump to be there, and he will take this opportunity to talk to 31 of our allies, plus our Indo-Pacific partners, about the importance of this commitment to spend, really, trillions of dollars on our combined and collective defence.”

Speculation has been rife that Trump could stay away from the summit on June 24 and 25 unless other member countries agree to raise their defence spending to at least 5% of GDP.

The current Nato baseline is 2%, but several countries fall short of this standard, while US spending has hovered around 3.5% for the last decade.

Whitaker said the 5% limit was “a necessity for our security”, but cautioned that raising spending alone was not enough. Nato members also needed to ramp up production and strengthen co-operation between the European and American defence industries.

“President Trump has been unwavering in his commitment to our collective security, and he has fundamentally changed the conversation on defence investment at NATO,” he said.

“This 5% investment plan will strengthen NATO’s ability to defer and defend against any threat, whether that’s conventional, nuclear, or even hybrid threats.”