'I promise not to do this to Greenland' - Donald Trump

US President Donald Trump has made a joke out of his idea to purchase Greenland from Denmark, tweeting a Photoshopped picture of Trump Tower in the middle of a desolate village.

"I promise not to do this to Greenland!" the President captioned the image on Monday. 

Trump has admitted he is "strategically" interested in acquiring the autonomous Danish territory - but Denmark's Prime Minister, Mette Frederiksen, has firmly denied the possibility of a sale.

"Essentially, it's a large real estate deal," Trump told reporters on Sunday.

"It's not number one on the burner, I can tell you that."

Trump's interest in owning the ice-covered territory was first reported by the Wall Street Journal last week.

White House economic advisor Larry Kudlow has since confirmed Trump's "strategic" interest in the world's largest island during an appearance on Fox News Sunday.

"The President, who knows a thing or two about real estate, wants to take a look at a potential Greenland purchases," Kudlow said.

Greenland's Ministry of Foreign Affairs have scorned the notion, reiterating they were "open for business, not for sale" on Firday.

Trump is to visit both Denmark and Greenland in September, regarding unrelated matters.

Newshub.