FILE - In this Monday, July. 31, 2017 file photo the sun sets over Nuuk, Greenland. A spokeswoman for Denmark's royal palace says U.S. President Donald Trump's decision to postpone a visit to Denmark next month was "a surprise." Trump announced his decision by tweet after the Danish prime minister dismissed the notion of selling Greenland to the U.S. as "an absurd discussion." (AP Photo/David Goldman, File)