At first, he joked about Canada being an additional US state. Since, he has threatened to take back control of the Panama Canal. He also reiterated a desire from his first term to own the autonomous Danish territory of Greenland, which is not for sale.

It's unclear how the issue of ownership of the Panama Canal became a talking point for President-elect Donald Trump this week, but the question has a long political history.

In recent days the president-elect has called for asserting U.S. control over the Panama Canal and Greenland, showing that his “America First” philosophy has an expansionist dimension.