A court spokesperson said the sentence against a co-defendant does not automatically cancel the charges against Adamov.
Adamov's defense lawyer said Thursday that a recent U.S. court ruling on a co-defendant in the case implied his client's case was dismissed.
U.S. authorities have charged the ex-minister with embezzling millions of dollars allocated in the 1990s to upgrade nuclear reactors in the former Eastern Bloc.
Genri Reznik said the federal court in Pittsburgh, which found co-defendant Mark Kaushansky guilty of tax evasion, also cleared Adamov of a $9 million embezzlement charge against him.
His view contradicts a statement from a spokesman for the U.S. attorney for the Western District of Pennsylvania, who said the charges against Adamov were still pending.
The Russian lawyer insisted: "Prosecutors are all alike. I have studied the court ruling carefully and it unequivocally implies that Adamov was exonerated."
Reznik said the Pittsburgh court found that there had been no conspiracy between Adamov and Kaushansky, a Russian nuclear engineer who now has Pennsylvania residency, and who was handed a 15-month prison term Thursday for personal and corporate tax evasion, and given a $20,000 fine.
Kaushansky, 56, was not convicted of involvement in the misappropriation of funds allocated by Washington as part of international financing for the upgrade of Soviet-era nuclear power plants.
As part of a plea Kaushansky entered in September, money laundering and other charges were dismissed.
Following the ruling, Adamov's defense lawyers said the charges against their client had also been dropped.
The Russian business daily Kommersant Friday cited a source in the Pittsburgh court as saying the ruling did not mention Adamov directly, but implied that there was no conspiracy to misappropriate the funds.
Reznik said earlier that the funds had been transferred to banks in the U.S. to protect it from the risks of Russia's ailing financial system in the early 1990s.
Adamov, 60, who served as nuclear minister in 1998-2001, was arrested in Switzerland in May 2005 at the request of the United States, and extradited to Russia in early 2006.
The defendant, who was released on bail in Russia, still faces fraud and abuse of office charges in Russia. He denies all accusations against him.
Adamov's lawyer said the Russian Prosecutor General's Office should now drop the charges against his client.
U.S. District Judge Maurice Chill was quoted as saying that Adamov "will probably never be in the United States to have the charges against him resolved." He previously ruled that Adamov may not be tried in absentia.
