Vasily Aleksanyan, 36, has been diagnosed with AIDS and cancer. One of his lawyers who was admitted for a visit on Saturday and Monday said his client had told him he was normally kept chained to the bed, and was only released when he had visitors.
"He is handcuffed to bed when there is no other way to secure him from an attempt to escape or suicide," Penitentiary Service spokesman Alexander Sidorov said. "He is also handcuffed when he has visitors in his room, and when he leaves the room he is handcuffed to a guard."
The decision to move Aleksanyan, 36, who has been accused of embezzling about $330 million from former Yukos production unit Tomskneft and shares worth $493 million from other oil companies, as well as of laundering stolen assets, was made following demands from lawyers and former colleagues.
Genri Reznik, a lawyer for Aleksanyan, said his defendant was satisfied with the treatment at the hospital.
"As we were told... this hospital is the only one in Moscow which can provide treatment for the conditions which Aleksanyan is suffering from," the lawyer said.
The prosecution earlier insisted he should undergo medical treatment in jail. However, a Moscow court suspended Aleksanyan's trial due to his worsening health.
Jailed ex-Yukos CEO Khodorkovsky, the founder of what was once Russia's largest oil producer, declared a hunger strike on January 30 demanding medical treatment for Aleksanyan. He called off his protest some two weeks later when Aleksanyan was admitted to hospital.
Aleksanyan earlier claimed that that the reluctance of the Russian authorities to provide him with medical treatment was due to his refusal to assist prosecutors with new charges against Khodorkovsky.
Yukos collapsed after claims of tax evasion in 2004 which led to the company being broken up and sold off to meet creditor claims. The bulk of its assets were bought through liquidation auctions by government-controlled oil company Rosneft. Yukos was officially dissolved in 2007.
