The statement came as a response to a question from a reporter at the White House, in connection with the president signing a number of decrees.
Greenland is a fantastic place, and we need it to secure international security. I'm sure Denmark will go along with it.
He said that Denmark has several reasons to review its relationship with Greenland.
It has cost them a lot to have it, and the people of Greenland are not satisfied with the Danes, they like us, he said.
However, Greenland was not mentioned in the speech that the President of the USA held on Monday, when he was sworn in as the new president.
Already during Trump's previous term, the American president showed interest in buying Greenland from Denmark, which was rejected. Before the current takeover, he brought up the issue again, and did not rule out economic sanctions or military power if he didn't get his way.
Neither Denmark nor Greenland has expressed interest in selling the island to the USA, although both parties have said they are open to discussing and cooperating with the USA.
Last week, Denmark's Prime Minister Mette Frederiksen had a 45-minute long phone call with Donald Trump, which, among other things, dealt with his ambitions to take control of Greenland.