Denmark's foreign minister has summoned the top US diplomat in Copenhagen, following a report that American citizens have been conducting covert operations in Greenland, BBC reported.

Denmark's public broadcaster DR quoted sources as saying the aim was to infiltrate Greenland's society and promote its secession from Denmark to the US, although it was unable to clarify who the men were working for.

Danish intelligence warned Greenland was being targeted by "various kinds of influence campaigns".

Foreign Minister Lars Lokke Rasmussen said "any attempt to interfere in the internal affairs of the Kingdom [of Denmark] will of course be unacceptable", and the US charge d'affaires had been summoned in that light, according to BBC.