President Donald Trump warned NATO that the U.S. needs Greenland for national security, saying that Russia or China would take it otherwise.

The Trump administration has repeatedly said the U.S. should be in control of Greenland, which is part of Denmark and NATO.

Greenland is an autonomous territory of the Kingdom of Denmark, which is a member of the U.S.-led NATO. Last week, Trump hinted at potential action.

Russia's ambassador to Denmark has accused NATO of seeking to militarize the Arctic amid US demands for control over the largely autonomous territory of Greenland, which is part of the Kingdom of Denmark.

President Donald Trump’s lust for Greenland may be the final nail in NATO’s coffin. His threat to invade the Arctic island is more than a game-changer. It’s a game destroyer. The North Atlantic Treaty Organisation (NATO) alliance is built around a central premise.

Ask many key European leaders and officials, and they will tell you the US is the bedrock of the NATO alliance. A key issue is Article 5 in the treaty, which says an attack on one is an attack on all. With Greenland part of Denmark, and Denmark being a NATO member, this creates a clear problem.

Less than one in five Americans approve of the efforts to acquire Greenland, and only one in 10 think the U.S. military should use force to do so, according to a Reuters/Ipsos poll this week.

President Donald Trump is talking about taking over Greenland by any means necessary. Republicans in Congress are trying to scare him back to reality. As Trump continually threatens to bring the Danish territory into the U.