Khodorkovsky, a billionaire oligarch who posed a challenge to Vladimir Putin early in his presidency, was convicted Monday of stealing oil from his own company and laundering the proceeds.
U.S. Secretary of State Hillary Clinton led a chorus of political figures in the United States and Europe in condemning the ruling, saying that it raised "serious questions about selective prosecution and about the rule of law being overshadowed by political considerations."
The Russian Foreign Ministry said the claims were unfounded and accused the West of trying to put pressure on the court.
"We expect everyone to mind their own business - at home and in the international arena," the ministry statement said.
The sentence, expected to be announced before the end of the week, is likely to keep Khodorkovsky behind bars for several more years. The judge on Tuesday continued to read his verdict, a lengthy summary of the 20-month trial.
The foreign ministry said the case against Khodorkovsky and his business partner Platon Lebedev involved serious charges of tax evasion and money laundering, crimes that are punishable under the law in any country.
"In the United States, by the way, people are given life sentences for such crimes," the ministry statement said.
This was an echo of a recent statement by Putin, now prime minister, that Khodorkovsky's punishment was less harsh than the 150-year prison sentence handed down in the U.S. to disgraced financier Bernard Madoff, who cheated thousands of investors with losses estimated at around $20 billion.
"Everything looks much more liberal here," Putin said.
Khodorkovsky is nearing the end of an eight-year sentence after being convicted of tax fraud in a case seen as punishment for challenging the Kremlin's economic and political power, in part by funding opposition parties in parliament.
Putin, who was president at the time and is seen as the driving force behind the legal attack on Khodorkovsky, has not ruled out a return to the presidency in 2012. He appears unwilling to risk the possibility that a free Khodorkovsky could help unite and lead his political foes.
The White House said it was troubled by what appears to be "an abusive use of the legal system for improper ends" and said the ruling hurts Russia's ability to improve ties with the United States.
The Obama administration has worked to "reset" ties with Russia under President Dmitry Medvedev, who has promised to strengthen the rule of law as part of his mission to modernize Russia and increase foreign investment. But Khodorkovsky's conviction demonstrates how little has changed in Russia since Medvedev succeeded Putin more than two years ago.