At Oslo district court, concrete manufacturer Olen Betong accused the Norwegian internal (PST) and external (E-tjeneste) intelligence services of contacting two employees working in the Murmansk region in order to turn them into informants.

The company, which has business in Russia's north-west, said the intelligence services had made repeated indiscrete contact over the last decade and that this was noticed by Russian government agencies.

Olen Betong claimed this led to the loss of an important contract in Russia and legal trouble for company founder Atle Berge and employee Kurt Sto.

The pair were arrested and interrogated in Murmansk before being declared persona non grata in Russia for ten years.

The company's lawyer Per Ristvedt said the case was unique in Norwegian judicial history.

“Norway has and should have an intelligence service. But it cannot be allowed to operate in a way that puts private individuals and companies at too much risk,” Ristvedt told the court, broadcaster TV2 said.

“There has to be a limit,” he added.

Olen Betong is seeking 140 million Norwegian kroner (13.7 million euros) in damages from the state.

Although the state admits that contacts were made by the intelligence services, it maintains they did not act carelessly and that discussions about security were part of normal operations.

“Norwegian intelligence has only done its job,” attorney general Fredrik Sejersted reportedly said in opening remarks in court.

The trial is set to take five days and feature ex-foreign minister and current Labour opposition leader Jonas Gahr Støre.

Another witness is Frode Berg, who was imprisoned in Russia but released last year in a spy swap.

Berg was jailed for 14 years after admitting to acting as a courier for Norwegian intelligence.

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