WASHINGTON – Yes, President Donald Trump is really considering purchasing Greenland.

"We're looking at it," Trump told reporters Sunday. "It's not No. 1 on the burner."

That's despite the fact that Greenland's government told Trump on Friday that the island was "not for sale."

The Wall Street Journal first reported on Thursday that Trump floated the idea of buying Greenland, an autonomous Danish territory.

It had been unclear whether Trump was joking or not. The Associated Press said Trump's interest in Greenland was characterized by "varying degrees of seriousness."

Trump said the "concept came up" and he found it interesting.

"Strategically, for the United States, it would be nice," he said. Plus, he said, Denmark is "carrying" Greenland "at a great loss."

Trump said that if he ends up visiting Denmark for other reasons during a September trip to Europe, he will "certainly talk about it" with Denmark officials.

"Essentially, it's a large real estate deal. A lot of things could be done," he said. "First we have to find out whether or not they have any interest."

Sen. Joe Manchin, D-W.Va., a member of the Senate Armed Services Committee, said Sunday his panel should be briefed on the idea if it's under serious consideration.

"That was a very interesting proposal that was thrown out," Manchin said on CBS' "Face the Nation." "If it has any merit to it, we’ll hear about it. I haven’t heard that. I’ve just heard basically what’s been reported on the news."

White House economic adviser Larry Kudlow said Sunday that the issue is "developing."

"I don’t want to predict an outcome," Kudlow said on "Fox News Sunday." "I’m just saying: The president, who knows a thing or two about buying real estate, wants to take a look at a Greenland purchase."

He called Greenland a "strategic place up there" with a "lot of valuable minerals."

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The United States proposed buying Greenland from Denmark in 1946 for $100 million, the AP and the Journal reported. The United States maintained weather stations and military facilities on the island during World War II.

The United States maintains a large military base – Thule Air Base – in Greenland. It is the U.S. military's northernmost installation, 750 miles north of the Arctic Circle.

Kudlow called Denmark a U.S. ally.

Greenland's Ministry of Foreign Affairs tweeted Friday that although Greenland is open for business, "we’re not for sale."

Appearing on "Fox News Sunday" after Kudlow, Montana Gov. Steve Bullock promoted a website his presidential campaign created: isgreenlandforsale.com.

"No," the rudimentary site tells visitors. "But while you're here, donate a buck to kick Donald Trump out of office."

Contributing: Nicholas Wu