OSLO - Danish Prime Minister Mette Frederiksen on Wednesday said that any interference in Denmark's internal affairs and in Greenland is "unacceptable," following reports that American citizens with ties to the White House are involved in covert influence activities in Greenland.

Earlier in the day, Danish broadcaster DR reported that at least three US citizens connected to President Donald Trump have been conducting influence operations in Greenland, including establishing private networks and compiling lists of local figures based on their stance toward US control of the Arctic island.

"We have a very clear disagreement when it comes to Greenland. Any interference in the internal affairs of the Kingdom of Denmark, and in Greenlandic democracy, is unacceptable," Frederiksen told the media, stressing that her government takes the matter "very seriously."

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The prime minister also noted that Washington has not explicitly denied the allegations. "I take note that the Americans have not clearly rejected what has been reported today. That is, of course, serious," she said.

Frederiksen said she had raised the issue with US senators at a meeting attended by Greenland's Foreign Minister Vivian Motzfeldt. "We have made it very clear that this is unacceptable, and we will communicate this message directly to our colleagues in the United States," she said.

The Danish Foreign Ministry confirmed that Foreign Minister Lars Lokke Rasmussen summoned the US charge d'affaires on Wednesday for talks regarding the reports.

"We are aware that foreign actors continue to show an interest in Greenland and its position in the Kingdom of Denmark. It is therefore not surprising if we experience outside attempts to influence the future of the Kingdom in the time ahead," Rasmussen said.

The minister said that the talks would be a "preventive conversation" aimed at making Denmark's position clear. "Any official involvement in activities that can be described as influence campaigns would be in violation of international rules."

Interference in the country's internal affairs is "unacceptable," he stressed.

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Responding to DR's request for comment, a representative of the US government said that "the US government does not control or direct the actions of private citizens," and that Washington "respects the Greenlandic people's right to decide their own future."

Since taking office earlier this year, Trump has repeatedly expressed interest in gaining control of Greenland, stating he would not rule out the use of "military or economic coercion" to achieve that goal.

The Danish Security and Intelligence Service told media that Greenland has increasingly been the target of influence campaigns aimed at creating tension between Copenhagen and Nuuk, Greenland's capital.

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Greenland, a former Danish colony, became an integral part of the Kingdom of Denmark in 1953. It was granted home rule in 1979, expanding its autonomy, though Denmark retains authority over foreign affairs and defense.