Greenland’s elected leader said the gigantic Arctic island is not for sale after Donald Trump once again raised the issue of “ownership and control” of the vast territory that has been part of Denmark for more than 600 years.

“Greenland is ours. We are not for sale and will never be for sale. We must not lose our long struggle for freedom,” Greenland’s prime minister, Múte Egede, said in a written comment.

The US president-elect on Sunday announced that he had picked Ken Howery, a former envoy to Sweden, as his ambassador to Copenhagen, and commented on the status of Greenland, a semi-autonomous part of Denmark.

“For purposes of National Security and Freedom throughout the World, the United States of America feels that the ownership and control of Greenland is an absolute necessity,” Trump wrote on Truth Social.

Trump, who takes office on 20 January, did not elaborate on the statement.

For many observers Trump’s comment triggered a sense of deja vu. During his first term Trump suggested in 2019 that the US should buy Greenland – which is home to the strategically important Pituffik US space base.

That idea was roundly rejected by Denmark as well as by the island’s own authorities before any formal discussions could take place. It also prompted widespread ridicule and became emblematic of the chaos that Trump brought to traditional global diplomacy – something now expected to happen again once Trump returns to the White House next month.

The Danish prime minister, Mette Frederiksen, in 2019 labelled Trump’s first offer as “absurd”, leading the then US president to describe her as “nasty” and to cancel a visit to the Danish capital of Copenhagen.

Separately on Sunday, Trump also threatened to reassert US control over the Panama Canal, accusing Panama of charging excessive rates to use the Central American passage and drawing a sharp rebuke from Panamanian president, José Raúl Mulino.

Reuters contributed reporting

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