Nuclear experts from Russia, the United States and Europe met secretly in the Bernese Oberland last week, the Swiss foreign ministry has confirmed.
The talks focused on the dismantling of the last three military nuclear reactors on Russian soil.
Swiss foreign ministry spokesman, Ivo Sieber, told swissinfo that Switzerland had only played host to the meeting and that no national experts had participated.
The talks were held at the national defence establishment, the Spiez Laboratory, and had been arranged at the request of Washington and Moscow.
Sieber stressed that discussions had mainly taken place between the Americans and Russians, and had focused on the technical aspects of dismantling the reactors in question.
He declined to comment on the outcome of the talks.
The Fribourg-based newspaper, La Liberté, revealed on Saturday that the talks had taken place.
It said that the Russians were keen to dismantle the reactors but lacked the technical know-how and the funds to do so.
Two of the reactors are located in Severesk, Siberia, and a third is in Zhelenogorsk, and they all still provide electricity to neighbouring regions, according to the newspaper.
They were once part of a network of 13 nuclear plants, which processed plutonium destined for the nuclear weapons of the former Soviet Union.
The paper claims that the Americans failed to keep their promises to the Russians, made after the end of the Cold War, to help them get rid of these plants and to build up other sources of energy.
At some point, the Swiss decided to play the role of intermediary by organising last week’s talks.
La Liberté added that the Russian ministry of atomic energy was looking for $89 million (SFr107 million) to finance the project.
Citing a Norwegian source, the paper said that about $500 million was needed to make the transition to other energy sources.
Spiez Laboratory is the Swiss defence establishment, dealing with nuclear, biological and chemical weapons.
It is concerned with the protection from nuclear, biological, and chemical threats and risks and with technical aspects of arms control and disarmament.
It supports peace-keeping measures with its technical expertise.
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