Snow-covered mountains rise above the harbour and town of Tasiilaq, Greenland. File picture: Lucas Jackson/Reuters

Washington - US President Donald Trump has repeatedly expressed interest in buying the entire island of Greenland "with varying degrees of seriousness," the Wall Street Journal (WSJ) reported Thursday.

The WSJ cited unnamed advisers as saying that the president asked White House counsels to "look into the idea" of purchasing the world's largest island.

The report said that Trump, who is scheduled to make his first visit to Denmark early next month, asked advisers whether the US could acquire Greenland on numerous occasions and expressed interest in the autonomous Danish territory's resources and geopolitical importance.

The WSJ cited current and former White House officials as saying Trump's intentions may be to strengthen military presence in the Arctic or to leave an Alaska-type legacy.

While the White House and State Department didn't respond to a request for comment from the WSJ, CNN cited two unnamed sources as confirming the report.

With a population of around 56,000, the icy territory between the North Atlantic and Arctic oceans is mostly self-ruled, though Denmark remains in charge of foreign affairs, defence and monetary policy.

Greenland receives some 560 million dollars in annual subsidies from Denmark, amounting to more than half of the territory's revenues.

This isn't the first time the US has set its sights on Greenland. In 1946, under president Harry Truman, the US offered Denmark 100 million dollars to buy the 2 million-square-kilometre island - an offer the Danes refused.