US Vice-President JD Vance will join his wife Usha in travelling to Greenland on Friday, a visit that follows Donald Trump's threats to take over the island.

The couple will go to the Pituffik Space Base to receive a briefing on Arctic security issues and meet members of US forces stationed there, according to the White House.

Usha Vance had planned to travel to the Danish territory on a cultural visit before her husband announced his plans. Trump's National Security Adviser Mike Waltz is also set to visit this week on a separate trip.

Officials in Greenland have fiercely criticised the planned visits as disrespectful.

Greenland - the world's biggest island, situated between the Arctic and Atlantic Oceans - has been controlled by Denmark, nearly 3,000km (1,860 miles) away, for about 300 years.

It governs its own domestic affairs, but decisions on foreign and defence policy are made in Copenhagen. The US has long held a security interest and a military presence there since World War Two.

The Pituffik Space Base, located in the north-west of Greenland, supports missile warning, air defence and space surveillance missions.

In a video posted on social media platform X, Vance said there was a lot of excitement around his wife's trip to Greenland. He is joining her because he "didn't want her to have all that fun by herself".

He said the visit to the military installation was to check on the island's security, as "a lot of other countries have threatened Greenland, have threatened to use its territories and its waterways to threaten the United States, to threaten Canada, and of course, to threaten the people of Greenland".

He added that the Trump administration wants to "reinvigorate the security of the people of Greenland", and that the United States and Denmark have ignored it for "far too long".

It is unclear if Mike Waltz is still scheduled to visit. The BBC has reached out to the White House for confirmation.

Dr Dwayne Ryan Menezes, founder and managing director of Polar Research and Policy Initiative think tank, based in London, criticised the visit.

He said it is "highly unusual" that a high-level delegation of US officials are visiting Greenland without being invited, especially after a national election in the country, where the parties are still in talks to form the next government.

The US' interest in Greenland's security, given its strategic importance, makes sense, he said. But he added that it is "inexplicable" for Washington DC to have taken such an aggressive approach, especially in light of Trump's comments about acquiring the territory.

"Disrespecting the people of Greenland by saying the US will acquire it 'one way or the other' is unhelpful and counter-productive as a tactic," he added.

According to recent polls, almost 80% of Greenlanders back independence from Denmark. But an opinion survey in January suggested an even greater number rejected the idea of becoming part of the US.