Swiss prosecutors have asked the United States to extradite a former Kremlin aide, Pavel Borodin, who is suspected of money laundering. Borodin was arrested on a Swiss warrant in New York on January 17.
A spokesman for the justice ministry, Raimund Renggli, said the extradition request has been forwarded to the US authorities.
Borodin is being held without bail in New York, where he is awaiting extradition to Switzerland.
Swiss prosecutors accuse him of laundering $25 million (SFr41 million), which he allegedly received from two Swiss firms in return for granting lucrative contracts to renovate the Kremlin.
Borodin denies any wrongdoing, as have the two Swiss firms - Mabetex and Mercata - which are implicated in the case.
Swiss prosecutors are pressing ahead with the case in the face of Russian pressure. Last week, the Russian foreign minister, Igor Ivanov, on a visit to Bern, asked Switzerland to bring the matter to a close as soon as possible.
But the Swiss foreign minister, Joseph Deiss, said at the time that the case was a "legal matter and not a political affair", and that the government's hands were tied by Swiss law which prevents any political interference in judicial matters.
Russia last year closed its investigation into the case, saying there was not enough evidence to proceed. That decision was criticised at the time as being politically motivated.
swissinfo with agencies