Donald Trump has repeatedly expressed an interest in annexing Greenland and again suggested Canada could become a US state.

President Trump had a “firm” phone conversation with Denmark’s prime minister last week to convey his serious intentions of acquiring Greenland, according to a report citing officials privy to the talk.

President Donald Trump told Denmark ’s prime minister he is serious about taking over Greenland in a “fiery” phone call last week, the Financial Times reports. Trump and Mette Frederiksen spoke on the phone for 45 minutes last week after the president said he wanted the US to take Greenland, despite officials repeatedly saying it’s not for sale.

From the Reconstruction era to the Cold War, multiple administrations have tried (and failed) to acquire the Arctic island. Here’s why Greenland has always remained out of reach—and why it always mattered so much.

The story goes that Trump and Frederiksen spoke on the phone last week for about 45 minutes in what was expected to be a bit of a feeling-out between the two parties, given Trump’s very public declaration that he would like to take Greenland off Denmark’s hands.

During last week's tense call with the Danish premier, Trump insisted he was serious about taking over Greenland, the Financial Times reported, raising fears about the future of trans-Atlantic relations.

Anders Vistisen, a Danish member of the European Parliament, has told U.S. President Donald Trump to "f*** off" after Trump again expressed interest in purchasing the island of Greenland. Newsweek has contacted the White House for comment via email.

The picturesque country of Greenland has become a popular destination for the many seniors who are traveling in record numbers to all corners of the world.

It “would send a strong signal and could contribute to stability in the region,” Robert Brieger, head of the EU’s highest military body, tells Welt am Sonntag.

President Trump has reiterated his desire to acquire Greenland, refusing to rule out the possibility of using military or economic coercion to achieve his goals. However, he isn't the only one with an interest in the region.

“Mr. Prime Minister, have you spoken to President Trump yet?” I asked as he fled a lunchtime news conference on Tuesday in the capital city, Nuuk (population 20,000). Egede, who is 37, wore a green zip-up sweater, stared straight ahead, and was walking toward me. He said nothing.