Greenland is not for sale, Danish Prime Minister Mette Fredriksen said on Monday, after U.S. Secretary of State Marco Rubio said last week that President Donald Trump's interest in acquiring the island was "not a joke".

Mette Frederiksen, the country’s prime minister, hints at concessions but still insists landmass is not for sale

Greenland is a self-ruling territory in the Danish kingdom, which means policymakers in Nuuk control most domestic issues. Denmark, which oversees defense and security policy on the mineral-rich Arctic island, is injecting 14.6 billion kroner ($2 billion) to ramp up defenses.