Greenlanders on Wednesday shrugged off US President Donald Trump's vow to take over the Arctic island, seeing it merely as an opportunity to advance their own independence bid.

In the quiet hallways of the University of Greenland in Nuuk, the capital of the Danish autonomous territory, Trump's latest remarks that he would take over Greenland "one way or another" left locals largely unfazed, despite his more menacing tone this time.

"For me personally, it's just something ridiculous he would say, but I wouldn't take it seriously because he's basically all talk and no action," said 23-year-old law student Peter Malik Henningsen.

"That sounds very violent and it's also very dumb... because Denmark, and Greenland, is also an ally of America," he said.

In his first major policy speech on Tuesday since returning to power, Trump underlined his expansionist vision, reiterating the importance of the United States taking over the strategically-located and mineral-rich Arctic island and taking back the Panama Canal.

About a quarter the size of the mainland US, Greenland's location in the Arctic puts it on the shortest route for missiles between Russia and the US.

Less than a week before general elections in Greenland where independence has dominated the campaign, Trump said he had a message for the island's 57,000-strong population, whom he described as "incredible people".

"We strongly support your right to determine your own future, and if you choose, we welcome you into the United States of America," Trump said.

But he then made clear he would not give up if persuasion fails, saying: "One way or the other we're going to get it," insisting the island was needed for reasons of national security.

Trump offered to buy Greenland already during his first term as president - in vain.

Since returning to the Oval Office in January, he has put the topic back on the agenda, and has this time said he wouldn't rule out military force to get it.

"Trump is like that, a bit unpredictable at times but I'm not worried," said another law student, David Jensen.

"We're part of Nato, the United States are part of Nato, so I'm not worried," insisted the 20-year-old who hails from one of the northernmost regions of Greenland. (AFP)