WASHINGTON (TNND) — President Donald Trump on Friday threatened to impose more tariffs on countries that don't support his plan to control Greenland.

Speaking at a White House roundtable event about tariffs on pharmaceutical imports from the EU, Trump mentioned, " I may put a tariff on countries if they don’t go along with Greenland, because we need Greenland for national security."

For months, the president has insisted the U.S. should control Greenland, a semiautonomous territory of NATO ally Denmark. Earlier this week, Trump said anything less than the U.S. having total control of the Arctic island is "unacceptable."

Recently, troops from five European countries were deployed to Greenland for a two-day mission meant to strengthen NATO allies’ "footprint in the Arctic."

“As part of the NATO alliance, it is a core priority for the Government of Greenland that defense and security in and around Greenland are strengthened, and that this is achieved in close cooperation with our NATO allies,” Greenland’s Minister of Foreign Affairs and Research Vivan Motzfeldt said.

The foreign ministers of Denmark and Greenland also met this week with Vice President JD Vance and Secretary of State Marco Rubio in Washington.

That encounter didn’t resolve the big differences, but did produce an agreement to set up a working group — on whose purpose Denmark and the White House then offered sharply diverging public views.