Greenland is at the centre of a new security agreement announced by U.S. President Donald Trump, who says Washington has reached a deal with Denmark and Greenland to strengthen the American military role on the Arctic island.
The announcement came Friday, September 18, 2026, after months of tension over Trump’s demands for greater U.S. control and access in Greenland. The agreement described by Trump would preserve the island’s place within the Kingdom of Denmark while giving the United States a permanent role in protecting Greenland and addressing American security concerns.
Denmark’s government presented the development more cautiously. It said Greenland, Denmark and the United States are expected to sign an agreement on strengthened security in the Arctic and North Atlantic next week during the United Nations General Assembly.
Table of Contents
What Trump announced about Greenland
Trump said the United States had entered into an agreement with Denmark and Greenland that would give Washington permanent control over security and other needs on the island.
He also said the arrangement would prevent U.S. adversaries from establishing a military base, maintaining a military presence or making sensitive investments in Greenland without American approval.
The president’s description has not been matched by a publicly released treaty text. That means the exact scope of any new U.S. rights, including access, construction, operations and investment restrictions, remains unclear.
Trump’s announcement also does not mean the United States has acquired Greenland or gained sovereignty over the territory. Greenland remains part of the Kingdom of Denmark, and the Danish government said the expected agreement recognizes the kingdom’s sovereignty and territorial integrity as well as the Greenlandic people’s right to self-determination.
Denmark and Greenland say signing is still ahead
A statement from Denmark’s Prime Minister’s Office said the three governments are expected to sign the agreement next week. It added that the agreement would still require the necessary national parliamentary procedures before it could enter into force.
That distinction is important. Friday’s announcement represents a political understanding or planned agreement, not a completed treaty that is already legally operative.
Greenland’s chairman of Naalakkersuisut, Jens-Frederik Nielsen, said the proposed agreement recognizes Greenland’s interests and its role in international co-operation. Danish Prime Minister Mette Frederiksen said the arrangement would strengthen security for Greenland, Denmark, the United States, NATO and Europe.
The official statement did not publish detailed provisions covering troop numbers, new installations, command arrangements, investment screening or the role of Greenlandic authorities in future U.S. activities.
Why Greenland matters to North American security
Greenland occupies a strategically important position between North America and Europe. Its location supports surveillance and defence planning across the Arctic and North Atlantic, while its proximity to emerging shipping routes and critical mineral resources has increased international interest.
The United States already has a military presence at Pituffik Space Base, formerly known as Thule Air Base, under a longstanding defence relationship with Denmark. The base supports missile warning, missile defence and space surveillance functions.
Denmark and Greenland have also been increasing attention on Arctic surveillance, sovereignty and resilience. The proposed agreement would therefore build on an existing defence framework rather than create the first American military relationship with Greenland.
The announcement comes as Arctic security becomes more closely linked to NATO planning, Russian military activity and concern about Chinese influence, infrastructure investment and access to strategic resources.
What happens next
The next major step is an expected signing during the United Nations General Assembly in the week beginning September 21, 2026. The final text will determine whether the agreement matches Trump’s broad description or sets out more limited and co-ordinated responsibilities.
Parliamentary procedures in the relevant jurisdictions will also matter. Until those steps are completed, the agreement should be treated as announced but not fully implemented.
For Canada, the development is significant because Greenland sits within the wider Arctic security environment shared by Canada, the United States and Denmark. Any increase in military activity, surveillance or infrastructure in Greenland could affect North American defence planning, Arctic shipping discussions and the security outlook around the Northwest Passage.
Canadian officials have not announced a separate response to the proposed arrangement. The immediate focus will be the text of the agreement, the role assigned to Greenlandic authorities and whether the final provisions expand the existing U.S. defence presence.
Frequently Asked Questions
Did the United States take control of Greenland?
No. Greenland remains part of the Kingdom of Denmark. Trump announced a proposed security arrangement, not a transfer of sovereignty.
Has the Greenland security agreement been signed?
Not yet. Denmark said Greenland, Denmark and the United States expected to sign the agreement during the United Nations General Assembly week beginning September 21, 2026.
What would the proposed Greenland agreement do?
Trump said it would give the United States a permanent role in Greenland’s security and prevent U.S. adversaries from establishing military or sensitive investment activities there without American approval. The detailed text has not been released.
Does the United States already have a base in Greenland?
Yes. The United States operates Pituffik Space Base under its defence relationship with Denmark.
Why is Greenland important to Canada?
Greenland’s location affects Arctic surveillance, North Atlantic defence, shipping routes and broader North American security planning, making any major change in its military posture relevant to Canada.
Fact-Checked: Key facts were checked against the Danish Prime Minister’s Office announcement and official information on the existing U.S. presence in Greenland.
Disclaimer: The proposed agreement remains subject to signing and required parliamentary procedures, and its final legal terms may differ from the initial political announcement.