The Swiss federal prosecutor, Valentin Roschacher, is holding talks with Russian officials over alleged corruption involving Swiss firms.
Roschacher met with the Russian Prosecutor General, Vladimir Ustinov, in Moscow to discuss two high-level corruption cases.
The first involves alleged bribes worth $62 million (SFr109 million) paid by the Swiss construction company, Mabetex, to top Moscow officials in former President, Boris Yeltsin's administration. The alleged kickbacks were in exchange for lucrative renovation work on the Kremlin.
One of the officials suspected of accepting bribes, the former Kremlin property manager, Pavel Borodin, has denied any wrongdoing.
The second case concerns the alleged embezzlement of hundreds of millions of dollars from the Russian airline, Aeroflot. The funds are said to have been channelled through Swiss companies.
The Russian business tycoon, Boris Berezovsky, is implicated in the Aeroflot case. Both he and the airline deny the allegations.
No charges have been made in Russia in either case. An arrest warrant was issued against Berezovsky last year, but was later dropped.
Roschacher's visit was initiated by the Swiss, who have complained that Russia has been slow to pursue the investigations.
The Moscow enquiry has also been complicated by the recent resignation of the former Russian prosecutor, Nikolai Volkov. He stepped down just weeks after travelling to Switzerland in July to collect documentation relating to the Aeroflot case.
Roschacher has taken more documents to Russia.
swissinfo with agencies
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