WASHINGTON -- US Secretary of State Marco Rubio said Wednesday that he plans to meet with Danish officials next week over the US demand to own Greenland.

"I'll be meeting with them next week ... We'll have conversations with them then," Rubio told reporters at the US Capitol.

"Every president always retains the option" of military force, but "we always prefer to settle it in different ways," he said, trying to downplay the White House statement from Tuesday. In an emailed statement, White House Press Secretary Karoline Leavitt told Xinhua that "utilizing the US military" is always an option for US President Donald Trump over his demand for Greenland.

Danish Foreign Minister Lars Lokke Rasmussen and Greenland's Foreign Minister Vivian Motzfeldt earlier officially requested a meeting with Rubio to discuss the crisis. Both Greenland and Denmark have made clear that the island is not for sale.

However, Rubio told lawmakers in a closed-door briefing on Monday that Trump's recent threats against Greenland did not signal an imminent invasion and that the White House's goal is to buy the island from Denmark, according to US media outlets.

Danish Prime Minister Mette Frederiksen, supported by European leaders, warned on Monday that "if the US chooses to attack another NATO country militarily, then everything stops, including NATO and thus the security that has been established since the end of the Second World War."

Trump said Wednesday on Truth Social that he is doubting whether NATO would come to US defense when it is needed.

Denmark is a member of both NATO and the European Union.