The United States, Denmark and Greenland have signed a new security agreement allowing Washington to expand its military presence on the Arctic island. The deal covers the modernisation of Pituffik Space Base and the creation of additional defence areas, while formally reaffirming Greenland’s position within the Kingdom of Denmark and its right to self-determination.
US President Donald Trump, Danish Prime Minister Mette Frederiksen and Greenlandic Prime Minister Jens-Frederik Nielsen signed the agreement in New York on 22 September 2026, on the sidelines of the United Nations General Assembly. The arrangement places Greenland’s security at the centre of wider Arctic and North Atlantic defence planning.
What the Greenland security deal allows
According to the Danish Foreign Ministry’s published terms, the agreement permits the United States to enlarge and modernise its existing facility at Pituffik, formerly known as Thule Air Base. It also provides for the establishment of new defence areas at Narsarsuaq and Mestersvig.
The agreement gives US forces broad operational access between designated defence areas. This includes movement by land, air and sea, as well as access involving Greenland’s territorial waters. US aircraft will also be permitted to fly over and land in any part of Greenland under the terms described in the agreement.
Key elements include:
- Expansion and modernisation of Pituffik Space Base.
- New defence areas at Narsarsuaq and Mestersvig.
- US access and movement between defence areas across Greenland.
- Permission for American aircraft to overfly and land throughout the island.
- Recognition of Denmark’s sovereignty and Greenland’s territorial integrity.
- Recognition of Greenland’s right to self-determination.
Agreement stops short of US control of Greenland
The deal follows months of political tension over Greenland’s strategic importance. President Trump had previously argued that American control of the island was necessary for US national security and had described the agreement as giving Washington permanent control over Greenland’s security.
However, the text reported by the Danish authorities does not transfer sovereignty to the United States. Instead, it explicitly reaffirms the sovereignty and territorial integrity of the Kingdom of Denmark while acknowledging Greenland’s right to determine its future.
That distinction is politically significant. Greenland has extensive self-government, but foreign and defence policy remain matters linked to the Kingdom of Denmark. The new arrangement therefore expands US military access without constituting a transfer of ownership or sovereignty.
Why Greenland matters to Arctic and North Atlantic security
Greenland occupies a strategically important position between North America and Europe. Its location makes the island relevant to early-warning systems, space surveillance, transatlantic communications and the monitoring of activity in the Arctic.
Pituffik Space Base is the northernmost US Department of Defense installation. The US Space Force identifies its functions as including missile warning, missile defence and space surveillance. Modernising the base and adding further defence areas could strengthen the ability of the United States and its partners to monitor the region.
The agreement also reflects growing attention to the Arctic, where changes in the security environment have increased the importance of infrastructure, surveillance and military mobility. Any expanded activity will remain politically sensitive because Greenland’s status, resources and future have become subjects of international strategic interest.
Responses from Denmark and Greenland
Both the Danish and Greenlandic governments welcomed the agreement. Frederiksen said it would strengthen common security in the Arctic and North Atlantic, while Nielsen described it as beneficial to all involved.
Their support indicates that the agreement was presented as a security partnership rather than a change in Greenland’s constitutional position. The inclusion of Greenland’s right to self-determination is particularly important in a political context where questions about the island’s future relationship with Denmark remain sensitive.
From Cold War presence to a renewed US role
The United States maintained a much larger military footprint in Greenland during the Cold War. The source agreement states that the US had 17 military facilities and more than 10,000 troops on the island at the height of that period.
Today, the US operates one confirmed base there: Pituffik Space Base. The new agreement could therefore mark a substantial expansion of access and infrastructure, although the published terms do not specify the number of additional troops, the construction timetable or the final size of the new defence areas.
What happens next?
The immediate next step will be implementation of the agreement by the United States, Denmark and Greenland. Further details will be needed on construction, funding, environmental rules, local consultation and the practical operation of the new defence areas.
The arrangement is not an EU decision. Greenland is outside the European Union, although it remains constitutionally linked to Denmark, an EU member state. The deal nevertheless has wider European significance because it concerns Arctic security, the North Atlantic and the defence relationship between a key European ally and the United States.
Conclusion
The Greenland security deal gives the United States wider military access and enables the expansion of facilities at Pituffik, Narsarsuaq and Mestersvig. At the same time, it preserves the stated sovereignty of the Kingdom of Denmark and Greenland’s right to self-determination. Its lasting importance will depend on how the new defence arrangements are implemented and how Greenland, Denmark and the United States balance strategic security with local political authority.
