Nato chief and former Dutch prime minister Mark Rutte has backed the continued central role of the United States in European security in an interview with the Financieele Dagblad, saying Nato and Europe cannot do without American support, even in the long term.

Speaking after a turbulent week on the international stage, Rutte told the paper any suggestion that Europe could protect itself without the US was unrealistic. “If anyone thinks we can just do without America for a while – forget it,” Rutte said. “The American nuclear umbrella is our ultimate security guarantee.”

Rutte has been in the spotlight after helping to defuse tensions sparked by “takeover” remarks from US president Donald Trump about Greenland. Trump later spoke of a possible “framework” for a deal after talks with Rutte and abandoned extra tariffs, a shift that international media attributed in part to the Nato chief’s behind-the-scenes diplomacy.

Rutte said the underlying issue was not sovereignty over Greenland, but the collective security of the Arctic. The region, he told the paper, has been a strategic concern for Washington for years, given Russian military activity and growing Chinese ambitions.

“The security of the Arctic as a Nato responsibility is highly relevant,” he said.

Rutte declined to comment publicly on sensitivities in Denmark and Greenland, saying disputes between allies are best handled privately. “As soon as I start saying what I think about the issues between allies, my ability to solve things disappears,” he said.

Rutte also reiterated his call for Nato countries to move towards spending 5% of GDP on defence. Europe, he said, must accelerate arms production, support defence start-ups drawing lessons from the war in Ukraine and convert parts of existing industry to military use.

He also dismissed the idea that Europe could soon replace US military power. Even with Britain and France as nuclear states, he said, they are “small” compared with the arsenals of the US and Russia. Without America, Europe would need to spend as much as 8% or 9% of GDP on defence, he said.

Despite criticism of his diplomatic style, Rutte said he remains focused on results rather than approval. “I don’t need to win a popularity prize,” he said. “I get energy from solving problems.”

“I will continue to focus on the job and who I am,” he said. “This summer there was a lot of fuss about the ‘daddy’ comment and that text message from Trump. It’s fine by me if everyone thinks whatever they like about it. I will do my job my way.”