The United States on Tuesday accused Kazakhstan of using its justice system to "silence opposition voices" after a prominent critic of Kazakh President Nursultan Nazarbayev was jailed for inciting violence.
Vladimir Kozlov was found guilty Monday of colluding with a fugitive billionaire in a failed attempt to rally oil workers to bring down the government of the Central Asian state.
Kozlov was sentenced to 7 1/2 years in prison and had his property confiscated. He has called his case an "undisguised attempt" to stifle protest and labor rights.
"We note our concern regarding the prosecution of Vladimir Kozlov and the apparent use of the criminal system to silence opposition voices," the U.S. Embassy said in a statement.
The criticism will hit home in Kazakhstan, which is a strategic ally of the United States.
Kazakhstan's Foreign Ministry said the trial had been fair and open to everyone.
"I disagree strongly with the politically motivated insinuations about the alleged lack of a fair and impartial judgment," said Altay Abibullayev, spokesman for the ministry.
Judge Berdybek Myrzabekov said Kozlov had politicized a labor dispute under orders from Mukhtar Ablyazov, an archrival of Nazarbayev and the self-exiled former head of BTA bank.