Donald Trump announced on Friday that the US had struck an Arctic security pact with the leaders of Denmark and Greenland, after threatening for months to take Greenland by force.

The US president cast the deal as a personal triumph, claiming in a post on Truth Social that the “very important, historic, and special” agreement “gives the United States permanent control over security, and all other needs, in Greenland, completely addressing ALL of our many U.S. concerns”.

“We will immediately begin the process of developing a large Military presence in the appropriate part of Greenland,” Trump added. The US already has a presence on the island, and the right to expand bases, through Nato.

Greenland is a self-governing territory of the Kingdom of Denmark, a fellow Nato member.

In his post, Trump said that the agreement means “no US 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”.

The US and Denmark will formally sign the agreement next week, on the sidelines of the United Nations general assembly in New York City, according to the Danish government.

Statements from Denmark’s prime minister, Mette Frederiksen, and the leader of Greenland’s government, Jens-Frederik Nielsen, posted online late Friday, emphasized that the agreement would fall far short of Trump’s stated desire for “the acquisition of Greenland by the United States”.

Frederiksen said that the agreement “recognizes the sovereignty and territorial integrity of the Kingdom and the right of the Greenlandic people to self-determination”.

Nielsen said the agreement “ensures and strengthens the security of Greenland, the Kingdom of Denmark, the United States and the Western alliance”, suggesting that the deal might possibly just reiterate the existing US rights through Nato to use the island as a security base.

Once agreed to, the pact will need to go through parliamentary procedures to be enacted, the statement said.

At a Nato summit in Ankara earlier this year, Trump renewed his bid for the US to acquire Greenland, threatening to pull all American armed forces out of Europe after the continent repeatedly pushed back.