However, a new target is likely to be agreed at a NATO summit in The Hague in June, spurred by fears that Russia may attack a NATO country after Ukraine and by Trump’s exhortations, officials said. The key open questions are what that new target will be and whether it will be enough to satisfy Trump.

Ralf Stegner, a member of Germany's Social Democratic Party, called Trump's comments "delusional and truly insane." Poland has backed Trump's demand.

A Polish soldier holds a Nato flag at a ceremony last year. Warsaw doubled its defence spending after Russia launched its full-scale invasion of Ukraine in 2022 © Wojtek Radwanski/AFP/ Poland backs Do

NATO allies are unlikely to meet U.S. President-elect Donald Trump's proposed spending target of 5% of GDP but are open to an increase from the current 2%, Reuters reported on Jan. 10, citing comments from officials and analysts from various NATO countries.