"I see that there are these tensions at the moment, there's no doubt. Again, I'm not going to comment on that, but I can assure you, the only way to deal with that is, in the end, thoughtful diplomacy," Rutte said at the World Economic Forum.

"You can be assured that I'm working on this issue behind the scenes, but I cannot do it in public."

The alliance head is set to meet Trump in the Swiss ski resort as the president's push to take over Greenland from Denmark has rocked NATO.

Rutte has sought to deflect Trump's interest in the Danish autonomous territory into a broader discussion at NATO on bolstering Arctic security.

"When it comes to the Arctic, I think President Trump is right. Other leaders in NATO are right. We need to defend the Arctic," he said.

Rutte dismissed fears that the crisis over Greenland could cause to the collapse of the 76-year-old alliance.

"NATO is crucial, not only for the defence of Europe, but also for the defence of the United States," he said.

"For the United States to stay safe, you need a safe Arctic, a safe Atlantic and a safe Europe."

The NATO secretary general pushed back at repeated comments from Trump casting doubt on whether Europe would help defend the United States if asked.

"I tell him, yes they will," Rutte said.

"I have no doubt the US will come to the rescue here, and we will come to the rescue of the US."

Speaking alongside Rutte in Davos, Finnish President Alexander Stubb said he believed a diplomatic solution could be found on Greenland.

"You have two schools of thought here on Greenland. One is to de-escalate, and the other one is to escalate, to de-escalate. And I think at the end of the day, we'll find an off ramp," he said.

Trump has threatened to slap tariffs on European allies who oppose his designs on Greenland -- leading the European Union to mull hitting back against Washington with trade countermeasures.