President Donald Trump has announced a new security agreement involving the United States, Denmark and Greenland that would allow Washington to significantly expand its military presence on the strategically important Arctic island.
Trump said on Friday, September 18, 2026, that the agreement gives the United States what he described as permanent control over Greenland’s security and other related needs.
He also announced that the US would immediately begin preparations for what he called a large Military presence in an appropriate part of Greenland.
The announcement marks a significant development in the long-running dispute over Greenland, which Trump has previously sought to bring under US control.
In a post on Truth Social, Trump said the agreement would ensure that the United States would have the ability to take whatever measures it considers necessary to defend Greenland and US security interests.
He also said the agreement would prevent US adversaries from establishing military bases or maintaining a military presence in Greenland, as well as making sensitive investments there without American approval.
Trump described the agreement as addressing all of Washington’s major security concerns and said it would come at “NO COST” to the United States.
However, the full text of the agreement was not immediately made public, leaving some details about its legal scope and implementation unclear.
The proposed expansion would build on an existing American military presence on the island.
The United States has maintained military access in Greenland for decades under a defence agreement with Denmark. The US operates Pituffik Space Base in northwestern Greenland, which has strategic importance for missile warning, space surveillance and communications.
The new agreement would reportedly provide Washington with broader and more permanent access, basing and overflight rights while strengthening restrictions on military activity by countries considered US adversaries.
Despite Trump’s previous demands for the United States to acquire Greenland, the new agreement does not transfer sovereignty over the territory to Washington.
Greenland remains part of the Kingdom of Denmark, while the island has extensive self-government and has continued to pursue its right to self-determination.
Trump’s latest announcement therefore represents a shift from his earlier push to acquire Greenland outright toward an arrangement focused primarily on security and military access.
Reuters reported that the agreement falls short of Trump’s earlier ambition to make Greenland part of the United States.
Danish and Greenlandic officials have presented the agreement as a framework for strengthening security in the Arctic and North Atlantic.
Greenland’s Prime Minister Mette Frederiksen said the arrangement recognises the sovereignty and territorial integrity of the Kingdom of Denmark as well as the Greenlandic people’s right to self-determination.
The Danish government has also said the agreement is intended to strengthen security cooperation in the Arctic and North Atlantic regions.
Greenland occupies a strategically important position between North America and Europe and is located along key Arctic and North Atlantic routes.
Its location has made the territory increasingly important to the United States and its NATO allies as military competition and geopolitical interest in the Arctic grow.
The island is also considered strategically significant because of its proximity to North America and the Arctic approaches, while its natural resources have attracted growing international attention.
Although Trump has described the arrangement in sweeping terms, important details remained unclear following his announcement.
Questions include the precise legal powers granted to Washington, the scale and location of any new US military facilities, and how the agreement will interact with Greenland’s self-government and Denmark’s sovereignty.
Reuters reported that the agreement would significantly enhance the US military footprint while keeping Greenland outside American territorial control.
The development is expected to remain a major issue in Arctic security discussions as the United States, Denmark and Greenland work through the details of the new arrangement.
