Observers doubt the new US president will buy the world's largest island but his interest underlines its strategic importance President Donald Trump's claim that US ownership and control of Greenland is "an absolute necessity" has underlined the strategic importance of the world's largest island in terms of American missile defences and anti-submarine operations.

We need it for international security. And I’m sure that Denmark will come along — it’s costing them a lot of money to maintain it, to keep it,” says new U.S. president.