It was a contentious, aggressive telephone call, five days before the inauguration of President Donald Trump on Jan. 20.

What drives the United States’ bold geopolitical ambitions toward Greenland and Canada? It boils down to economic and national security.

President Donald Trump has said he believes the US will gain control of Greenland, after showing renewed interest in acquiring the autonomous Danish territory in recent weeks. "I think we're going to have it," he told reporters on Air Force One on Saturday, adding that the island's 57,000 residents "want to be with us".

The story goes that Trump and Frederiksen spoke on the phone last week for about 45 minutes in what was expected to be a bit of a feeling-out between the two parties, given Trump’s very public declaration that he would like to take Greenland off Denmark’s hands.

The people of Greenland 'want to be with us', US President Donald Trump has said. The US president is threatening economic sanctions against Denmark if it does not agree to sell Greenland to the US. The Arctic island belongs to Denmark but enjoys a large degree of autonomy.