The US Greenland security agreement is done, at least in principle. Donald Trump announced on 19 September 2026 that the United States, Denmark and Greenland have reached a deal granting the US ‘permanent control over security, and all other needs, in Greenland’, with a formal signing expected at the UN General Assembly the following week.
The announcement ends months of escalating pressure from Washington. Trump had previously called on Denmark to sell the island, repeatedly threatened annexation, and argued Greenland was indispensable to US national security. Denmark and Greenland consistently replied the island was not for sale.
What the US Greenland security agreement actually covers
Trump posted the announcement on Truth Social, stating the deal means ‘no U.S. adversary can EVER have a base in Greenland, have a military presence in Greenland, or make sensitive investments in Greenland, without our express written approval.’ He described it as an ‘Infinite Life Agreement, there is no end’ and said the US would ‘immediately begin the process of developing a large Military presence in the appropriate part of Greenland.’
According to OpenAgreements, the 2026 deal allows expansion at Pituffik Space Base in northwestern Greenland and establishes additional defence areas at Narsarsuaq and Mestersvig. That goes well beyond the existing footprint. The US already has more than 100 military personnel permanently stationed at Pituffik, and those new locations extend American military reach further into the island’s interior and southern regions.
US Secretary of State Marco Rubio called it a ‘historic deal’ and a ‘huge win for the United States and the American people’, adding: ‘This deal permanently and completely addresses our national security concerns in Greenland.’
Denmark and Greenland’s position
The tone from Copenhagen and Nuuk was markedly more measured. In a joint statement with Greenland’s government, Danish Prime Minister Mette Frederiksen said she was ‘pleased that there is a prospect of a good agreement’ for all three parties. The deal, she said, ‘strengthens our common security in the Arctic and the North Atlantic area’ while also recognising ‘the sovereignty and territorial integrity of the Kingdom and the right of the Greenlandic people to self-determination.’
Frederiksen confirmed both Denmark and Greenland expect to sign the agreement the following week but did not outline the full contents publicly. The framing from Copenhagen centres on security cooperation rather than a transfer of control, reflecting a line both governments have held throughout the dispute.
Trump, by contrast, framed it as a historic personal achievement. ‘For over 100 years, Presidents have known the strategic importance of Greenland, but NONE of them were able to do anything about it,’ he wrote. ‘I am proud to be the President that permanently and conclusively addressed this very important situation.’
Arctic stakes: missiles, minerals and the Golden Dome
The deal sits inside a broader strategic picture. Trump has said Greenland is essential to his plan to build a Golden Dome defence system designed to protect the US against missile attacks from Russia and China, and that European allies could cooperate in the endeavour.
There is also the resource dimension. Greenland holds vast and largely untapped reserves of rare earth minerals, many of which are crucial for technologies including mobile phones and electric vehicles. Those reserves have long drawn interest from multiple quarters, and the agreement’s clause restricting foreign investment without US approval directly targets that competition.
With expansion at Pituffik and new defence areas at Narsarsuaq and Mestersvig confirmed by the agreement’s terms, the formal signing at the UN General Assembly will be the next concrete step in what Trump called ‘a dream come true for the United States of America.’