Greenland, Denmark and the United States signed a new defense agreement on September 22, 2026, updating the 1951 Greenland defense treaty and clearing the way for two additional US defense areas on the island.
The six-page agreement was signed by Naalakkersuisut chairman Jens-Frederik Nielsen, Danish Prime Minister Mette Frederiksen and US President Donald Trump. DR reports that Nielsen described it as an agreement that brings the 1951 defense agreement into 2026. The full text has been published by the Danish Prime Minister’s Office.
According to the Prime Minister’s Office, the signing took place at the United Nations headquarters in New York. The office also states that the agreement must pass the necessary parliamentary procedures in Denmark and Greenland before it enters into force.
Two new defense areas
The agreement gives the United States permission to establish an additional defense area at Narsarsuaq in southern Greenland and at Mestersvig on the east coast. TV 2 notes that further defense areas beyond these would require approval from both Denmark and Greenland. Narsarsuaq previously housed the American base Bluie West 1, active from 1941 to 1958.
Mestersvig currently hosts a station under Arctic Command, used among others by the Sirius dog sled patrol. The United States today has one base in Greenland, Pituffik Space Base in the northwest. The new agreement allows Washington to modernize and expand its activities there.
The Danish Defence estimated in September 2025 that around 150 American soldiers were stationed at Pituffik, in addition to civilian employees. In the early 1950s, the site, then known as Thule Air Base, held close to 10,000 American soldiers and other staff.
Golden Dome, submarines and investment limits
The text mentions the establishment of a Golden Dome missile defense system, Trump’s planned large-scale missile shield. It also allows the United States to set up unmanned military installations. Reuters reports that the agreement has no end date and can be amended only by mutual consent under the 1951 procedures.
At the press conference following the signing, Frederiksen highlighted submarines as a new element. Submarine activity was not permitted under the 1951 agreement. Point 10 of the new text restricts investments in particularly sensitive sectors by states or investors from outside NATO, NATO partner countries and the EU.
The agreement states that Greenland has the right to decide its own future. If Greenland becomes an independent state, both the Danish and Greenlandic governments must ensure it commits to remaining in NATO, if necessary by applying for membership. An independent Greenland would also assume the Kingdom of Denmark’s rights and obligations under the agreement.
The formal title of the document describes it as amending and supplementing the agreement of April 27, 1951, on the defense of Greenland, along with later related supplementary agreements. The text refers to the Greenland defense agreement complex, including the 1951 agreement and the 2004 Igaliku agreement.
