OSLO - Danish Foreign Minister Lars Lokke Rasmussen said on Wednesday that he will summon the United States ambassador to Denmark for a meeting following media reports suggesting that Washington plans to intensify espionage activities targeting Greenland.

The move comes after The Wall Street Journal reported on Tuesday that US intelligence agencies have been instructed to identify individuals in Greenland and Denmark who support American strategic objectives for the Arctic island, citing anonymous sources.

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"I have read the article, and it worries me a lot - because we do not spy between friends," Rasmussen told Danish broadcaster DR on his way to a meeting of foreign ministers in Warsaw, Poland. Acknowledging that the report could not be verified, Rasmussen noted that it had not been strongly denied by US officials. "That worries me," he added.

He confirmed that the American ambassador will be summoned for talks at the Ministry of Foreign Affairs in Copenhagen. "The aim is to see whether we can have this somewhat disturbing information refuted - and in any case, to make our position clear. It is very concerning if the approach now involves gathering intelligence in Denmark and Greenland," Rasmussen said.

The reported espionage efforts have further strained US-Danish relations, already tense since US President Donald Trump repeatedly expressed interest in purchasing Greenland - a proposal that sparked political backlash throughout Denmark.

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"All people are impressionable. That's why it is serious if a good friend of Denmark and Greenland is speculating in gathering intelligence and exerting influence with the aim of weakening the unity of the Kingdom and taking over Greenland," Rasmussen said, adding that he did not believe the United States would succeed in such efforts.

Earlier on Wednesday, Denmark's domestic intelligence agency PET issued a written statement noting that there is "an elevated espionage threat and threat of foreign influence against both Denmark and Greenland" due to increased international focus on the region.

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