Donald Trump and Greenland: Why would he want to buy it?

Bad news Denmark, President Donald Trump won't be coming to visit in September, as planned.

Why? Prime Minister Mette Frederiksen has said she won't sell him Greenland - a massive island territory.

"Essentially it's a large real estate deal," he said on Sunday, but Denmark was having none of it.

Ms Frederiksen said the suggestion was "absurd" and a spokesperson for the Danish People's Party said this was "final proof he has gone mad."

So why would Donald Trump want to buy a territory that belongs to another country?

Greenland is part of the Arctic and it's estimated that 13% of the world's undiscovered oil reserves and 30% of its undiscovered gas lies under the Arctic.

And President Trump is a fan of fossil fuels.

In March 2017 he signed an executive order for every part of the US to loosen their rules on fossil fuels so that more could be mined, drilled for and used in America.

He doesn't believe climate change is a threat, and pulled the US out of the Paris Accord in 2017.

There is also believed to be vast mineral resources underground in Greenland, with mining opportunities for coal, zinc, copper and iron ore - among others.

Donald Trump loves building properties - and there's plenty of space in Greenland - it's the least densely populated country in the world.

There are approximately 56,500 people living in Greenland, and it's 2.1 million kilometres square.

For comparison, the UK has 67.5 million people, even though it's nearly nine times smaller in terms of land mass.

Oh, but there's a stumbling block in case there were any plans for a Trump Tower in Greenland - 75% of Greenland is covered in a permanent ice sheet.

That could make building work tricky.

Sure, Greenland is owned by Denmark and part of Europe, but it's close to North America and there were suggestions the USA could buy it in the 1860s.

US President Harry Truman offered Denmark $100m for Greenland in 1946. There was even talk of swapping some parts of Alaska for bits of Greenland.

When asked about his interest in trading US land with Denmark, Mr Trump said "a lot of things could be done."

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