The prime minister says the "hard yards" of bolstering Arctic security can begin after the US president's shift.

Leaders of Denmark and Greenland insisted Thursday that the island's sovereignty was nonnegotiable after U.S. President Donald Trump said he had agreed with the NATO chief on the framework of a future Arctic security deal that Trump said would grant the U.

Former NATO Secretary General and former Danish Prime Minister Anders Fogh Rasmussen warned Donald Trump that an attempt to conquer the Danish territory of Greenland would be the end of the Western alliance,

President Trump conceded the U.S. may not end up taking over Greenland, but said he's "getting everything" he wanted out of the Danish territory.

Trump said on Thursday he had secured total and permanent U.S. access to Greenland after ‌talks with Rutte, while the NATO chief said allies would have to step ​up ‌efforts to ward off ‍threats from ⁠Russia and China in the high north.