The Swiss president, Adolf Ogi, expressed his condolences on Wednesday for the relatives of the 118 sailors who died on board the flooded Russian submarine, Kursk.
The Swiss foreign ministry said that Ogi's thoughts were with the families of the submariners who lost their lives in the Barents Sea.
Ogi expressed his deepest personal sympathy for the bereaved in an official letter addressed to the Russian president, Vladimir Putin.
The comments of the Swiss president coincided with Russia's official day of mourning with thousands of citizens gathering at remembrance ceremonies across the country.
Norwegian marine experts said that the bodies of the sailors could not be recovered before the summer of next year
The Russian embassy in the Swiss capital, Berne, opened a book of condolence on Wednesday.
Viktor Borisenko, a political analyst working for the embassy, said: "Already in the morning many people began arriving. There were Russians, other nationalities and Swiss visitors". Borisenko also said numerous letters expressing sympathy had been received from the Swiss authorities and private individuals.
Putin, meanwhile, told the Russian people on television that he felt personally responsible for the tragedy
swissinfo with agencies
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