US President Donald Trump and his officials are “actively” discussing a potential offer to buy the Danish territory of Greenland, the White House has confirmed.

It is “something that’s currently being actively discussed by the president and his national security team”, White House spokeswoman Karoline Leavitt told reporters on Wednesday.

Both Greenland and Denmark have repeatedly stressed the island was not for sale.

Asked why the Trump administration had previously said it was not ruling out using military force to acquire Greenland, Leavitt replied that all options were always on the table but Trump’s “first option always has been diplomacy”.

Concerns over the future of the territory resurfaced after Trump’s unilateral use of military force against Venezuela on Saturday to seize its President Nicolás Maduro. Denmark, a fellow Nato ally, says an attack on its territory would end the military alliance.

The Trump administration says Greenland is vital to US security.

Despite being the most sparsely populated territory, its location between North America and the Arctic makes it well placed for early warning systems in the event of missile attacks.

Pituffik Space Base, formerly known as Thule Air Base, has been operated by the US since World War 2.

In recent years, there has also been increased interest in Greenland’s natural resources, including rare earth minerals, uranium and iron that are becoming easier to access as its ice melts due to climate change. Scientists think it could also have significant oil and gas reserves.

US Secretary of State Marco Rubio said on Wednesday that he will hold talks with Denmark next week.

Trump previously made an offer to buy the island in 2019, during his first presidential term, only to be told it was not for sale.

“The acquisition of Greenland by the United States is not a new idea,” Leavitt said.

“The president has been very open and clear with all of you and with the world, that he views it in the best interest of the United States to deter Russian and Chinese aggression in the Arctic region, and so that’s why his team is currently talking about what a potential purchase would look like.”

The White House said earlier this week that Trump had been discussing a range of options to acquire Greenland, including using military force.

“All options are always on the table for President Trump as he examines what’s in the best interests of the United States,” Leavitt said.

Earlier in the day, French Foreign Minister Jean-Noël Barrot said Rubio had “ruled out the possibility of an invasion” of Greenland in a phone call with him.

Barrot is due to discuss the Arctic island with his German and Polish counterparts later on Wednesday.

On Tuesday, European leaders issued a joint statement rallying behind Denmark.

“Greenland belongs to its people, and only Denmark and Greenland can decide on matters concerning their relations,” the leaders of France, the UK, Germany, Italy, Poland, Spain and Denmark said in a joint statement.

Stressing they were as keen as the US on Arctic security, the European signatories said this must be achieved by Nato allies, including the US, “collectively”.

They also called for “upholding the principles of the UN Charter, including sovereignty, territorial integrity and the inviolability of borders”.

A day after the US military action in Venezuela, Katie Miller, the wife of one of Trump’s senior aides, posted a map on social media of Greenland in the colours of the US flag, alongside the word “SOON”.

On Monday, her husband, Stephen Miller, said it was “the formal position of the US government that Greenland should be part of the US”.

Aaja Chemnitz, one of two MPs in the Danish parliament representing Greenland, told the BBC that the comments from the Trump administration were “a clear threat”.

“It’s completely disrespectful from the US side to not rule out annexing our country and to annex another Nato ally,” she said.

But Chemnitz said she saw this as unlikely – instead, “what we are going to see is that they will put pressure on us in order to make sure that they will take over Greenland over time”.

Aleqatsiaq Peary, a 42-year-old Inuit hunter living in Greenland’s remote northerly town of Qaanaaq, appeared indifferent to the potential of US ownership.

“It would be switching from one master to another, from one occupier to another,” he told the BBC. “We are a colony under Denmark. We are already losing a lot from being under the Danish government.”

Saying that he did not have “time for Trump”, he added that people were “in need”. Hunters like him, he explained, hunted with dogs on the sea ice and fish “but the sea ice is melting and hunters cannot make a living anymore”.

Additional reporting by Adrienne Murray in Copenhagen