President Trump on Thursday expressed confidence the United States would annex Greenland, even suggesting the head of the NATO alliance could be a key player in facilitating the acquisition.

"I think it will happen," Trump told reporters in the Oval Office during a meeting with NATO Secretary-General Mark Rutte.

And I'm just thinking, I didn't give it much thought before but I'm sitting with a man that could be very instrumental. You know, Mark, we need that for international security," Trump said, gesturing to Rutte.