The European Union can help provide security for Greenland, should Denmark request it, the European Commissioner for Defence and Space said, warning that a U.S. military takeover of the island would be the end of NATO.

The senator's comments come after President Donald Trump said the U.S. would "do something on Greenland, whether they like it or not."

Greenland will not accept a US takeover under “any circumstance” and demanded NATO insure its defense Monday amid President Trump’s desire to acquire the autonomous territory of

Trump’s threat to annex an autonomous part of Denmark has plunged NATO into an unprecedented situation: An alliance based on collective defense now faces the prospect that one member might attack another.

Top Trump aide Stephen Miller says it's the "formal position" of the White House that Denmark's territory of Greenland "should be part of the U.S."

NATO member countries are discussing and working on the next steps for how to collectively keep the Arctic safe, alliance chief Mark Rutte said on Monday.

The response comes amid concerns over Russia's continued military build-up in the region and its close ties to China.

It’s not for peaceful purposes,” U,S, Air Force Gen. Alexus Grynkewich said. “They’re not studying the seals and the polar bears."