Jailed Russian oil magnate Mikhail Khodorkovsky has been sent to a prison camp to serve the rest of his 13-year sentence.

Khodorkovsky's wife and lawyers were not allowed to meet with him before he was transferred to the undisclosed location. Russia has 753 prison colonies around the country.

Both Khodorkovsky and his jailed business partner Platon Lebedev recently had filed requests for parole.

The requests were rejected by a court for a lack of documents, and the two had been preparing an appeal.

Khodorkovsky and Lebedev had been serving time for tax evasion and fraud when they were given additional sentences in December for money laundering and stealing oil from their own company.

Supporters say the charges are politically motivated because Khodorkovsky, once one of Russia's richest citizens, supports politicians opposed to Prime Minister Vladimir Putin.

The European Court of Human Rights ruled last month that Khodorkovsky's rights were violated after his 2003 arrest, but rejected his claims that the detention was political in nature.