OSLO - Storebrand Asset Management, which has joined investor calls for a moratorium on seabed mining, has raised concerns with Kongsberg about the Norwegian company's stake in seabed minerals start-up Loke Marine Minerals, its CEO Jan Erik Saugestad said.

Critics of seabed mining, which is being driven by demand for copper, cobalt and rare earth elements, say that not enough research has been done into the industry's environmental impact and some investors have voiced their concerns about its effects.

Kongsberg, which has a 10% stake in Loke, is aware that seabed mining is a sensitive subject has had discussions about this with Storebrand and other unnamed stakeholders, a spokesman told Reuters on Friday.

"Kongsberg's motivation for being a part of Loke Minerals is that we have technology that can monitor and do surveillance on the seabed, to form a basis for decisions for sustainable harvesting of seabed minerals," he said.

Storebrand Asset Management, part of insurance group Storebrand, does not plan to divest its less than 1% stake in the Norwegian defence company, Saugestad told Reuters.

Saugestad said Norway's largest private asset manager was "in dialogue" with Kongsberg over its stake in Loke, which holds two exploration licences in the Pacific Ocean.

"We do believe it's not a wise long-term investment. It might prove to be, but we need much more insight to fully understand this business opportunity," Saugestad said.

"There needs to be more insight, there needs to be proper regulation in place before we open up for potential concessions," he added.

Loke Chief Executive Walter Sognnes said Kongsberg owned about 10-15% of the company he co-founded.

Sognnes told Reuters that Loke will seek to attract more investors to raise about $100-million needed to fund resource mapping, environmental studies and technology development.

He said he was concerned that Storebrand Asset Management's approach could scare away investors, and opposed a call for an international moratorium which the fund group backed in July.

"It's very easy to say we shouldn't touch the oceans. It would have been simple if we had much better alternatives," Sognnes said, adding: "We don't reduce our dependence on China by building battery factories, if minerals to build those batteries are still going to come from China," he added.

There is intense debate over seabed mining in Norway, which could become the first country to start commercial deep sea mining if a government plan is approved by its parliament.