Donald Trump’s decision to cancel a visit to Denmark next month after the prime minister described his plan to buy Greenland as “absurd” has taken the Danish royal palace by surprise, a spokeswoman said.

Lene Balleby said the news was “a surprise” to the royal household, which had formally invited the US president to visit Denmark on September 2 and 3 as part of a European trip.

Mr Trump announced his decision by tweet after the Danish prime minister dismissed the notion of selling the semi-autonomous territory to the US as “an absurd discussion”.

“Denmark is a very special country with incredible people, but based on prime minister Mette Frederiksen’s comments, that she would have no interest in discussing the purchase of Greenland, I will be postponing our meeting scheduled in two weeks for another time,” Mr Trump said.

There was no immediate reaction from the Danish government, but former government ministers were quick to speak out.

Martin Lidegaard, a former foreign minister, told broadcaster TV2 it was “a diplomatic farce” and said Mr Trump’s behaviour was “grotesque” and he was “throwing a hissy fit”.

The cancellation was “deeply insulting to the people of Greenland and Denmark”, former prime minister Helle Thorning-Schmidt wrote on Twitter.

Claus Oxfeldt, chairman of Denmark’s main police union, told Danish media that authorities had been busy planning the third visit by a sitting US president to the Scandinavian Nato member.

“As far as I know, it has created great frustrations to have spent so much time preparing for a visit that is cancelled,” he was quoted as saying.

Mr Trump had said on Sunday that he was interested in buying Greenland for strategic purposes, but said a purchase was not a priority. Ms Frederiksen and Greenland’s premier Kim Kielsen responded that Greenland is not for sale.

“The Prime Minister was able to save a great deal of expense and effort for both the United States and Denmark by being so direct,” Mr Trump said. “I thank her for that and look forward to rescheduling sometime in the future!”

White House spokesman Judd Deere later confirmed that the visit to Denmark had been cancelled. Mr Trump’s visit to Poland is expected to go ahead.

Kim Kielsen with Mette Frederiksen
Kim Kielsen with Mette Frederiksen (Mads Claus Rasmussen/Ritzau Scanpix/AP)

Greenland sits between the Atlantic and Arctic oceans, and a 660,000-square-mile ice sheet covers 80% of the island.

Retreating ice could uncover potential oil and mineral resources in Greenland which dramatically change the island’s fortunes. However, no oil has yet been found in Greenlandic waters and the thickness of the ice means exploration is only possible in coastal regions.

Even there, conditions are far from ideal, due to the long winter with frozen ports, 24-hour darkness and temperatures regularly dropping below minus 30C in northern parts.

It would not be the first time an American leader has tried to buy the world’s largest island. In 1946, the US proposed to pay Denmark 100 million dollars to buy Greenland after flirting with the idea of swapping land in Alaska for strategic parts of the Arctic island.

Under a 1951 deal, Denmark allowed the US to build bases and radar stations on Greenland.

The US Air Force has one base in northern Greenland, Thule Air Force Base, 745 miles south of the North Pole. Former military airfields in Narsarsuaq, Kulusuk and Kangerlussuaq have become civilian airports.

The Thule base, constructed in 1952, was originally designed as a refuelling base for long-range bombing missions. It has been a ballistic missile early warning and space surveillance site since 1961.