Denmark’s Prime Minister Mette Frederiksen has issued a strong warning to the United States after U.S. President Donald Trump once again made remarks about Greenland, a large island that is an autonomous territory within the Kingdom of Denmark.

On Monday, in response to Trump’s renewed interest in Greenland, Frederiksen firmly rejected the idea that Greenland should become part of the United States. She made her position clear during an interview with a Danish broadcaster, criticising Trump’s repeated claims that the U.S. “needs” Greenland for security reasons.

Frederiksen said, “Unfortunately, I think the American president should be taken seriously when he says he wants Greenland.” She stressed that both Denmark and Greenland have repeatedly ruled out any possibility of the island becoming part of the United States.

Her remarks came after Trump spoke about the strategic importance of Greenland during an interview with The Atlantic. In that interview, Trump said the United States “absolutely” needs Greenland, calling it very important right now. He claimed Greenland is strategic because it is “covered with Russian and Chinese ships all over the place.” He also said, “We need Greenland from the standpoint of national security, and Denmark is not going to be able to do it.”

When asked what would happen if the United States used force against another NATO member, Frederiksen gave a stark warning. She said, “If the U.S. attacks another NATO country, everything stops.” She explained that she could not predict what Washington might do, but she made it clear that Denmark believes NATO’s collective defence obligations must be respected.

Frederiksen added that while she could not say what actions the United States might take, “there is full support from Europe that borders must be respected.” This reinforced her belief that European allies stand with Denmark on this issue.

In response to Trump’s comments, Frederiksen also issued a separate statement on Sunday emphasising that the United States has no right to annex Greenland. She strongly urged Washington to stop issuing threats against a “historically close ally” and the people of Greenland.

The tensions have increased following Trump’s appointment of Jeff Landry, the Governor of Louisiana, as the U.S. special envoy to Greenland last month. Landry has publicly supported the idea of the United States taking control of the island, which adds to concerns among Danish and Greenlandic leaders.

Since returning to the office in January 2025, Trump has shown repeated interest in acquiring Greenland. He has not ruled out using military or economic pressure to pursue that goal. This pattern has alarmed officials in Copenhagen, who stress that Greenland falls under Denmark’s authority and is also covered by NATO’s defence framework.

What makes the situation particularly sensitive is that Greenland is a NATO member through Denmark’s membership, and the island holds important strategic value because of its geographic position between Europe and North America.

Analysts say Trump’s comments have stirred geopolitical concern because any talk about using force against a NATO member raises serious questions about collective defence obligations and alliance unity.

Frederiksen’s warning highlights the importance Denmark places on respecting international borders and NATO principles. Her message was clear: the U.S. should not threaten a NATO ally, and European countries are united in backing Denmark on this matter.