Denmark's foreign ministry told AFP on Monday it had “no comment” on a report by Danish public television DR, which said the espionage took place from 2012 to 2015.

That would suggest that the US spying, if confirmed, was going on during and after the 2013 Snowden affair, which erupted when former intelligence contractor Edward Snowden revealed that the US government was spying on its own citizens and its allies.

According to DR, the fresh allegations are based on internal Danish intelligence reports written by a whistleblower who wanted his superiors to act.

DR said its investigation showed the US National Security Agency (NSA) “took advantage of a top secret Danish-American surveillance collaboration to deliberately spy on central ministries and private companies in Denmark.”

The broadcaster reported that much of the espionage concerned the defence sector and in particular Denmark's tender for a new jet fighter to replace its ageing fleet.

Copenhagen ended up ordering 27 F-35s from US manufacturer Lockheed Martin, which beat out the Eurofighter and Sweden's Saab Gripen.

Other US allies, such as Germany, France, Norway, the Netherlands and Sweden, were also the targets of US espionage in the defence sector, DR's report said.

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