The judicial authorities in canton Geneva have turned down a proposed deal offered by Russia to obtain the release of a high-ranking official arrested on a Swiss warrant in New York.
Bernard Bertossa, Geneva chief prosecutor, said on Monday he would not agree to withdraw an international arrest warrant issued against Pavel Borodin on charges of money laundering.
"The procedures must be handled according to the legal framework," Bertossa told correspondents.
In return for Swiss cooperation, the Russian government had said it would guarantee that Borodin would give evidence at an appointed time, but Bertossa said Moscow did not have the legal means to ensure this.
FBI agents arrested Borodin on Wednesday as he arrived at New York's Kennedy Airport to attend a party celebrating George W. Bush's inauguration as US president. It was not clear who had invited him to the US.
He is being held without bail until a hearing Thursday. Switzerland is preparing a formal request for extradition.
Borodin, the Kremlin property manager under former President Boris Yeltsin, is accused of taking several million dollars' worth of bribes from two canton Ticino companies, Mabetex and Mercata, which had contracts to renovate Kremlin buildings. At least part of the money was allegedly laundered through Swiss accounts held by Borodin.
Russian prosecutors last year closed their investigation after more than two years, saying they did not have any evidence. The decision was criticised by Yuri Skuratov, as overtly political.
Bertossa also attacked the Russian move at the time, saying the case had been dropped because of Borodin's links with Russia's authorities. The Geneva investigators kept their own case open.
swissinfo with agencies