Switzerland's highest court has blocked the transfer of bank documents sought by Russia as part of Moscow's probe of the defunct Yukos oil company.
The Lausanne-based tribunal ruling came Thursday after an appeal from former Yukos managers seeking to stop the Swiss attorney-general from sharing the documents with Russian prosecutors.
Swiss news reports quote the high court as saying the Kremlin opened criminal cases against Yukos officials to remove political adversaries.
Yukos defendants, led by jailed former company chief Mikhail Khodorkovsky, have long argued that criminal charges brought by the Kremlin were aimed at silencing critics of President Vladimir Putin. The Kremlin denies the charges.
Prosecutors have accused Khodorkovsky and his associate, Platon Lebedev, of stealing more than $33 million from Yukos's subsidiaries.
Khodorkovsky and Lebedev are serving eight-year prison sentences and face additional money laundering charges.
Some information for this report was provided by AP and Reuters.