The prospect of American annexation has reinvigorated ties between the island and Copenhagen, though aspirations for independence persist.

President Donald Trump has renewed his threat of using military force to annex Greenland, saying in an NBC News interview he wouldn’t rule it out to make the self-governing Danish territory a part of the United States.

Danish Foreign Minister Lars Lokke Rasmussen said on Wednesday he would call in the acting U.S. ambassador to Denmark for talks after the Wall Street Journal reported Washington had ordered U.S. intelligence agencies to step up spying on Greenland.