US president Donald Trump has doubled down on his threats to take control of Greenland, saying on social media that there is no going back and that Greenland is imperative.

During a news conference at the White House, Trump was asked how far he was willing to go to acquire Greenland and replied, You'll find out.

Meanwhile, French president Emmanuel Macron warned at a meeting at the World Economic Forum in Switzerland of a shift towards a world without rules, while Canadian Prime Minister Mark Carney said the old order is not coming back.

Trump is due to arrive in Davos on Wednesday, where he has said there are a lot of meetings scheduled on Greenland.

During the lengthy press briefing, Trump also told reporters that things are going to work out pretty well in Greenland.

Asked by the BBC whether the possible breakup of the NATO alliance was a price the president was willing to pay for Greenland, he responded, Nobody has done more for NATO than I have, in every way, and said NATO is going to be happy and we are going to be happy, adding, We need it for world security.

But he earlier questioned whether NATO would come to aid of the US, should it be required.

I know we'll come to (NATO's) rescue, but I just really do question whether or not they'll come to ours, he told reporters.

NATO currently has 32 member states, with the US one of the 12 founding countries.

Trump has not ruled out using military force to acquire Greenland; when asked if he would use force, he replied no comment.

In an interview with BBC Newsnight on Tuesday evening, Greenland's Minister of Industry and Natural Resources, Naaja Nathanielsen, said that Greenlanders were bewildered by the president's demands.

We do not want to be Americans, and we have been quite clear about that, Nathanielsen said.

What value do you put on our culture and our right to decide what happens with us in the future?

Tuesday was the first day of the forum in Davos. The President of the European Commission, Ursula von der Leyen, addressed the matter directly, emphasizing that Europe is fully committed when it comes to the security of the Arctic.

However, she said this could only be achieved together, and criticized Trump's proposed additional tariffs as a mistake.

Trump has threatened to add a 10% tariff on goods imported from eight European countries if they opposed his takeover of Greenland.

Von der Leyen added that the EU stands in full solidarity with Greenland and Denmark, asserting that their sovereignty is non-negotiable.

Her words were echoed by Canada's Mark Carney, who emphasized his country's commitment to NATO's Article 5, which states an armed attack against one or more members is considered an attack against all.

Macron condemned Trump's approach as a form of bullying, favoring respect and the rule of law over brutality.

In further escalation, Trump has suggested imposing a 200% tariff on French wine and champagne after Macron declined an invitation to join a proposed board for peace in Gaza.

Macron is reportedly urging the EU to consider retaliatory options against US tariffs, while sources indicate the European Parliament may suspend approval of a US trade deal agreed in July, marking increased tensions between the US and Europe.