WASHINGTON -- US President Donald Trump said on Thursday that he believes the United States would annex Greenland, an autonomous territory of Denmark, during a meeting with NATO Secretary General Mark Rutte in the Oval Office, US news outlets reported.

Trump expressed confidence the United States would annex the large island, even suggesting the head of the NATO alliance could be a key player in facilitating the acquisition, The Hill reported.

"I think it will happen," Trump told reporters in the Oval Office during the meeting, said the report.

In response, Rutte said that any discussion about Trump's attempts to acquire Greenland is outside of his purview and he doesn't want to drag NATO in that, the report stated.

Trump also said "Denmark's very far away" from Greenland, despite being part of that country's kingdom, The Associated Press reported.

"A boat landed there 200 years ago or something. They say they have rights to it," Trump said in the Oval Office, adding that "I don't know if that's true. I don't think it is, actually," according to the report.

Trump noted that the United States already has a military presence in Greenland and, "Maybe you'll see more and more soldiers going there," the report added.

Since early this year, Trump has repeatedly stated his desire to obtain Greenland, even suggesting the possibility of using force.

Acknowledging the uncertainty sparked by Trump's moves, Danish Prime Minister Mette Frederiksen reaffirmed Denmark's position earlier this month, emphasizing that Greenland's future is solely for its people to decide.

Greenland's opposition Demokraatit (Democrats) party won Tuesday's parliamentary election, according to preliminary data released by the Central Election Committee on Wednesday. The party favors a gradual move toward independence from Denmark and has criticized Trump's threat to annex Greenland.

Greenland, the world's largest island with a population of around 60,000, was a Danish colony until 1953, when it became an integral part of Denmark with Greenlanders given Danish citizenship. In 1979, Greenland achieved home rule, gaining greater self-governance while Denmark retained authority over its foreign and defense policy.