
A BBC investigation has uncovered new evidence about corruptive agreements through which roman abramovich put the dastardly wealth.
Chelsea's owner earned billions after buying an oil company from the Russian government in a tender manipulated in 1995. Abramovich paid about $250 million to Sibneft, before selling it to the Russian government for $13 billion in 2005.
His lawyers say there is no basis to claim that he has accumulated very considerable wealth through criminality.
The Russian billionaire was sanctioned by the British government last week because of his ties to Russian President Vladimir Putin. Abramovich's powers have been frozen and he has been sacked as President of Chelsea.
The Russian billionaire has already admitted to a court in the Uk that he has made corruptive payments to secure the deal for Sibneft.
He was indicted in London by his former business associate, Boris Beresovsky in 2012.
Abramovich won the case, but he described in court how Sibneft's original auction was manipulated in his favor and how he gave Beresovsky $10 million to pay a Kremlin official.
BBC Panorama has provided a document thought to have been smuggled out of Russia.
The information was provided to the program by a confidential source, who says it was secretly copied from files held by Abramovich by Russian law enforcement agencies.
The document says the Russian government lost $2.7 billion in the Sibneft agreement - a claim backed by a 1997 Russian parliamentary investigation. The document also says Russian authorities wanted to accuse Abramovich of fraud.
It says: "Economic Crimes Department investigators concluded that if Abramovich could be brought to trial, he would have faced fraud charges within a structured criminal group."