MOSCOW — Jailed Russian oil tycoon Mikhail Khodorkovsky has declared a hunger strike, he said in an open letter to the chairman of Russia's supreme court published on Tuesday.

Khodorkovsky accused a Moscow court of unlawfully keeping him in jail as he awaits trial on new charges of financial crimes, which he said violated recent amendments to Russian law pushed through by President Dmitry Medvedev.

"I declare a hunger strike until I have confirmation that Dmitry Medvedev has received from you or another relevant official full information on the violation of" the recent amendments, Khodorkovsky said.

"I think it is critically important for President Medvedev to know exactly how the law he initiated is being observed -- or rather flouted -- by state officials," he said in the letter, published by Russian media.

"If the president agrees that the laws signed by him and passed by the parliament may be flouted by courts and other state officials as they see fit, I will submit to my current situation," the tycoon said.

But he added bitterly that "I will stay in jail anyway whatever the court decides."

Khodorkovsky's defence team confirmed that he was declaring a hunger strike in a statement on its website. The tycoon, who has been jailed since 2003, has previously held several brief hunger strikes.

The amendments signed by Medvedev in March prevent entrepreneurs from being jailed while awaiting trial on economic crimes and were aimed at keeping corrupt prosecutors from putting pressure on business.

Khodorkovsky, once Russia's richest man, is serving an eight-year prison sentence on fraud and tax evasion charges that he claims were politically motivated and is now facing trial on fresh charges that could see him jailed for 22 more years.

Supporters of Khodorkovsky say he was jailed because of his opposition to the policies of Vladimir Putin, who was president when the tycoon's legal problems began and who is now Russia's powerful prime minister.

The 46-year-old former head of the Yukos oil company now stands accused of stealing millions of tonnes of oil and laundering money.

Khodorkovsky, 46, says the new charges are a rehash of the original case against him and argues he is being prosecuted again because the corrupt officials who have seized control of Yukos fear seeing him go free.

The Russian government insists Khodorkovsky committed massive financial crimes during the controversial privatizations of the 1990s in which he and other so-called oligarchs acquired immense fortunes.

Copyright © 2010 AFP. All rights reserved.