COPENHAGEN - Greenland on Friday dismissed the notion that it might be up for sale after reports that U.S. President Donald Trump had privately discussed with his advisers the idea of buying the world's biggest island.

"We are open for business, but we're not for sale," Greenland's foreign minister Ane Lone Bagger told Reuters.

Trump is due to visit Copenhagen in September and the Arctic will be on the agenda during meetings with the prime ministers of Denmark and Greenland, an autonomous Danish territory.

Talk of a Greenland purchase was first reported by the Wall Street Journal. Two sources familiar with the situation told Reuters that the notion had been laughed off by some advisers as a joke but was taken more seriously by others in the White House.

Danish politicians on Friday poured scorn on the idea.

"It has to be an April Fool's joke. Totally out of season," former prime minister Lars Lokke Rasmussen said on Twitter.

"If he is truly contemplating this, then this is final proof, that he has gone mad," foreign affairs spokesman for the Danish People's Party, Soren Espersen, told broadcaster DR.

"The thought of Denmark selling 50,000 citizens to the United States is completely ridiculous," he said.

Greenland, a self-ruling part of Denmark located between the North Atlantic and Arctic oceans, is dependent on Danish economic support. It handles its own domestic affairs while Copenhagen looks after defense and foreign policy.

"I am sure a majority in Greenland believes it is better to have a relation to Denmark than the United States, in the long term," Aaja Chemnitz Larsen, Danish MP from Greenland's second-largest party Inuit Ataqatigiit (IA), told Reuters.

"My immediate thought is 'No, thank you'," she said. -Reuters