North Atlantic Treaty Organization Secretary General Mark Rutte demurred on Thursday when President Donald Trump baited him into backing his dream of the United States annexing Greenland. Rutte—who has been nicknamed NATO’s “Trump whisperer”—shared laughs with the president throughout their Oval Office meeting on Thursday.

The head of NATO is expected to speak with President Donald Trump in Washington, D.C., on Thursday. The meeting with NATO Secretary General Mark Rutte comes after Trump called on European allies to contribute more to the alliance’s defense fund.

President Donald Trump told NATO Secretary-General Mark Rutte on Thursday that U.S. control of Greenland is necessary to enhance international security, escalating his campaign to annex the strategic Arctic island.