Mikhail Khodorkovsky, a jailed Russian oil tycoon and once the country's richest man, has been transferred to Moscow ahead of a new trial on charges of fraud and theft.

The former head of oil giant Yukos was sentenced to eight years in a Siberian prison in 2005 on fraud and tax evasion charges.

A spokeswoman for Moscow City Court said on Tuesday that Khodorkovsky had been transferred to the capital, where preliminary hearings are due to begin on March 3.

Russian news agencies said Khodorkovsky and Platon Lebedev, his former business associate, were being charged with embezzling nearly $27.5bn.

The 2003 arrest of the oil billionaire generated interational controversy.

Vladimir Putin, who was Russian president at the time, was criticised by Western business figures who said Khodorkovsky was targeted because of his political ambitions.

Khodorkovsky has always maintained his innocence, saying he was the victim of corrupt officials under Putin who wanted to carve up his business empire.

Following Khodorkovsky's 2003 arrest, Yukos - one of the country's largest private firms- was broken up and its main assets sold off to a state-controlled company.