Greenland's prime minister has asked US President Donald Trump to talk to him instead of making "random outbursts on social media", after Trump said he was sending a US hospital boat to "take care" of people on the island.

Trump wrote on Truth Social that he was going to send a boat filled with medical supplies, alleging "many people" on the island are sick and "not being taken care of".

Jens-Frederik Nielsen responded "it's going to be a no thanks from us," and said that Greenland provides free healthcare for all citizens.

Trump has long coveted the vast arctic island - but conceded in January that he would not take it by force, after previously refusing to rule out doing so.