Switzerland’s highest court said that Russian legal proceedings against Mikhail Khodorkovsky, the jailed former chief executive of Yukos, were politically motivated and blocked the release to the Russian authorities of bank documents relating to the bankrupt oil company.

The Swiss federal tribunal, in a landmark ruling, found that Khodorkovsky and Platon Lebedev, his associate, were victims of political persecution and it rejected a request for assistance by Russian authorities in their pursuit of tax claims against Yukos.

The tribunal in Lausanne accepted arguments by lawyers representing the two men that the criminal proceedings were discriminatory and politically motivated.

In refusing to release the documents, the court referred to “concrete facts that lead to the inference that the appellant is under pursuit for hidden motives, notably in relation to his political opinions”. Moscow had opened the criminal case against Khodorkovsky to “sideline declared or potential political adversaries”, the court stated.

The Swiss ruling is the first time that a leading nonRussian tribunal has opined on merits of the Khodorkovsky case. The Yukos chief, who was once Russia’s richest man, was a vocal critic of President Putin. Khodorkovsky was convicted of tax fraud in 2004 and sentenced to eight years’ imprisonment in Siberia.

Swiss authorities ordered the release yesterday of about SwFr300 million (£124 million) held in bank accounts linked to the former Yukos owners. The case arose in 2003 when Russian authorities sought legal help from Switzerland in their pursuit of alleged fraud and money laundering in relation to Menatep, the holding company through which Khodorkovsky and his associates controlled Yukos. The oil company was bankrupted and dismembered by Russian authorities in pursuit of massive tax claims. The assets of Yukos were sold to Rosneft after several rigged auctions.

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