Greenland's new prime minister has said the island is not a "piece of property that can be bought", in response to Donald Trump's repeated calls for the US to take control of the autonomous Danish territory.

On a visit to Copenhagen on Sunday, Jens-Frederik Nielsen said Greenland and Denmark must stand together in the face of "disrespectful" US rhetoric.

He was speaking alongside Danish Prime Minister Mette Frederiksen in what has been viewed as another show of unity between the two leaders.

In a further symbolic gesture, Nielsen is due to return to Greenland on Monday with Denmark's King Frederik, who will begin his four-day royal visit to the island.

"We will never, ever be a piece of property that can be bought by anyone, and that's the message I think is most important to understand," said Nielsen, who became Greenland's prime minister this April.

He added that Greenland and Denmark needed to move closer together in light of the new foreign policy situation.

Trump has caused outrage in both Denmark and Greenland for repeatedly saying he wants to bring the Arctic island under US control.

During a speech to Congress in March, Trump said that control of Greenland was essential "for national security and international security".

He has floated the idea of buying the island and has previously refused to rule out using military force, though US Vice-President JD Vance said last month: "We do not think that military force is ever going to be necessary."

Despite their criticism of Trump's words, both Nielsen and Frederiksen on Sunday said they would be willing to meet the US president for talks.

Nielsen also reiterated that Greenland was prepared to deepen ties with the US, saying: "We are ready for a strong partnership and more development, but we want respect."

Nielsen's visit to Denmark follows Frederiksen's own trip to Greenland earlier this month.

"You can't annex other countries," was her message for the US president at the time.

It followed Vance's whirlwind visit to the territory, widely criticised in both Denmark and Greenland, in which he reiterated Trump's ambitions and claimed Copenhagen had "not done a good job" for Greenlanders.

Greenland, the world's largest island, has been controlled by Denmark for about 300 years. The island governs its own domestic affairs, but foreign and defence policy decisions are made in Copenhagen.

The US has long had a security interest in the island. It has had a military base there since World War Two, and Trump may also have an interest in the rare earth minerals that could be mined.

Polls show that the vast majority of Greenlanders want to become independent from Denmark but do not wish to become part of the US.

Formed in March, Greenland's new coalition government is led by Nielsen's centre-right Democrats party, which favours a gradual approach to independence.