US President Donald Trump is discussing options including military action to take control of Greenland, the White House said Tuesday, upping tensions that Denmark warns could destroy the NATO alliance.

Trump has stepped up his designs on the mineral-rich, self-governing Danish territory in the arctic since the US military operation to seize Venezuelan leader Nicolas Maduro last weekend.

White House Press Secretary Karoline Leavitt said that "acquiring Greenland is a national security priority" for Trump to deter US adversaries like Russia and China.

"The president and his team are discussing a range of options to pursue this important foreign policy goal, and of course, utilizing the US military is always an option at the commander in chief's disposal," she said in a statement to AFP.

The Wall Street Journal reported US Secretary of State Marco Rubio told lawmakers that Trump's preferred option is to buy Greenland from Denmark, adding that the threats did not signal an imminent invasion.

Denmark has warned that any move to take Greenland by force would mean that "everything would stop" including NATO and 80 years of close transatlantic security links.

Any US military action against Greenland would effectively collapse NATO, since the alliance's Article Five pledges that member states will defend any of their number that come under attack.

Greenland and Denmark said earlier that they had asked to meet Rubio quickly as tensions rose over the issue.

"It has so far not been possible," Greenland's Foreign Minister Vivian Motzfeldt wrote on social media, adding that they had been pushing for a meeting throughout 2025.

Denmark's Foreign Minister Lars Lokke Rasmussen said meeting Rubio should "clear up certain misunderstandings." 

Greenland Prime Minister Jens-Frederik Nielsen earlier insisted that the island was not for sale, and that only its 57,000 people should decide its future.

'Not acceptable'

Allies have rallied around Denmark and Greenland -- while trying not to antagonize Trump at the same time.

The leaders of Britain, France, Germany, Italy, Poland and Spain joined Denmark in a statement on Tuesday saying that they would defend the "universal principles" of "sovereignty, territorial integrity and the inviolability of borders."

French President Emmanuel Macron and British Prime Minister Keir Starmer both sought to play down the row as they attended Ukraine peace talks in Paris alongside Trump's envoy Steve Witkoff and son-in-law Jared Kushner.

"I cannot imagine a scenario in which the United States of America would be placed in a position to violate Danish sovereignty," Macron said.

Canadian Prime Minister Mark Carney, whose country Trump earlier this year said should become the 51st state, also weighed in.

"The future of Greenland and Denmark are decided solely by the people of Denmark and Greenland," Carney told reporters in Paris.

The United States already has a military base in Greenland, the Pituffik space base, with around 150 personnel stationed there.

Greenland residents have also rejected Trump's threats.

"This is not something we appreciate," Christian Keldsen, director of the Greenland Business Assocation, told AFP in the capital Nuuk. "It is not acceptable in the civilized world."

Trump's Deputy Chief of Staff Stephen Miller told CNN on Monday that "nobody's going to fight the United States militarily over the future of Greenland!"

Copenhagen has however invested heavily in security, allocating some 90 billion kroner ($14 billion) in the last year.

Trump has been floating the idea of annexing Greenland since his first term.

"It's like a broken record," Marc Jacobsen, a specialist in security, politics and diplomacy in the Arctic at the Royal Danish Defence College, told AFP.