Taking an expected slap at a long-time foe, Russian Prime Minister Vladimir Putin declared on Thursday that the crimes of former oil tycoon Mikhail Khodorkovsky have been proven and a “thief should sit in jail.”

Khodorkovsky is serving an eight-year sentence after being convicted of tax fraud and is awaiting a verdict in a second trial on charges of stealing oil from his own oil company that could keep him in prison for many more years.

Both cases have been seen as punishment for posing a political challenge to Mr. Putin as he was consolidating his power. Mr. Putin was in his first term as president when Khodorkovsky was arrested in 2003 after funding opposition parties.

Khodorkovsky’s supporters said Mr. Putin’s comments during his annual televised call-in show would just increase the pressure on the Moscow judge who is deliberating the Khodorkovsky case.

One of Khodorkovsky’s lawyers, Karinna Moskalenko, said Mr. Putin’s statements indicate that the judge will find Khodorkovsky guilty.

“This statement will have a whole host of implications,” she was quoted by the Interfax news agency as saying about Mr. Putin’s comments. “First of all, in the form of a guilty verdict.”

In addition to saying Khodorkovsky was guilty of economic crimes, Mr. Putin once again suggested the former oligarch ordered the killings of people who stood in his way. Khodorkovsky has not been charged with any violent crime.

Mr. Putin said the former security chief at Khodorkovsky’s Yukos oil company has been convicted of involvement in several killings.

“What? Did the security service chief commit all these crimes on his own, at his own discretion?” he said.

Mr. Putin said Khodorkovsky’s present punishment was “more liberal” 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,” Mr. Putin said. “Nevertheless, we should presume that Mr. Khodorkovsky’s crimes have been proven.”

The reading of the verdict in the second trial of Khodorkovsky and his partner Platon Lebedev had been scheduled for Wednesday but was delayed at the last minute until December 27. Khodorkovsky’s father expressed fears that this was done to let Mr. Putin have his final say on the case.

If convicted, Khodorkovsky and his partner Platon Lebedev face prison sentences of up to 14 years, which could keep them in prison until at least 2017.

Mr. Putin has not ruled out a return to the presidency in 2012, and critics suspect him of wanting to keep Khodorkovsky incarcerated until after the election.

The case as been seen as a test for President Dmitry Medvedev, who has promised to establish independent courts and strengthen the rule of law in Russia.

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