The Russian foreign ministry has called on Switzerland to return Moscow’s former atomic energy minister, who was detained in Bern earlier this month.
Yevgeny Adamov was arrested in the Swiss capital on a request from the United States, which wants to try him on fraud charges.
The Swiss justice ministry said on Thursday that Russia had filed an extradition request for Adamov.
The Russian bid is based on an arrest warrant by the authorities in Moscow which are investigating Adamov on suspicion of fraud, according to a statement by the ministry's Federal Justice Office.
In 2001 the Russian parliament accused the former minister of corruption and fraud during his time in office.
On Wednesday the Russian foreign ministry said that it would not grant a US extradition request, calling it "unacceptable".
Adamov is also wanted by US justice officials who have accused him of diverting up to $9 million (SFr11 million) from funds intended to improve security at Russia’s nuclear facilities.
The Swiss statement said that the Russian government had told Switzerland of its "serious concern" over the arrest, which it believed did not comply with international law, and had taken a raft of measures to secure his speedy return.
"We think that the criminal investigation of an ex-minister and former member of the Russian government on foreign territory and his extradition to a third country for this purpose breaches Russia's national security interests."
According to the Russian statement, if Adamov is suspected of committing crimes when he was in office, he should be able to claim immunity from foreign criminal prosecution.
If there is any case to answer, it added, it should be heard in Russia under Russian law.
The US authorities have charged Adamov with money laundering, tax evasion, conspiracy to defraud the US and conspiracy to transfer stolen money. He could face up to 60 years in prison and a fine of $1.75 million.
The Swiss justice ministry said it would examine which of the requests has priority.
The US has until the end of June to file an extradition request for the former minister.
Adamov’s lawyers have already appealed to Switzerland’s Federal Criminal Court against his arrest, saying it was illegal.
The 66-year-old Adamov had come to Switzerland to help his daughter regain access to blocked bank accounts and was arrested on May 2.
A Swiss citizen since 1992, Irina Adamova is the subject of a money-laundering investigation and has had her bank accounts frozen.
The accounts contain assets worth around SFr250,000 ($205,000).
There is believed to be no connection between the accusations against Adamova and those levelled against her father.
swissinfo with agencies
Former Russian President Yeltsin named Adamov atomic energy minister in 1998.
He kept his post in 2001 after a cabinet reshuffle under President Putin.
However, he was removed from the government later the same year due to corruption allegations.