A top court in France is refusing to hand a Kazakh banker turned dissident charged with embezzling billions over to Russia.
Mukhtar Ablyazov's lawyers had asked France's Council of State to block his extradition, fearing Russia would quickly send him back to Kazakhstan.
The Council of State said on Friday that it considered the extradition request to be "politically motivated".
The court noted that the Kazakh and Russian authorities have "repeatedly" held consultations on Ablyazov's case.
Ablyazov, a former Kazakh energy minister who founded an opposition party, is charged with stealing billions of tenge, the Kazakh currency, from a bank he founded, BTA. He was arrested in France in 2013.
Russia claims its citizens were defrauded in the collapse of the now-nationalised bank.
"We are thrilled with the result today,"Ablyazov's lawyer, Peter Sahlas, told The Associated Press. "This is a huge step forward for human rights law in France and Europe."
"The decision is unprecedented," he added.
Last year another French court, the Court of Cassation, had approved Ablyazov's extradition. The French government signed an extradition decree in September 2015, but Ablyazov appealed to the Council of State, France's highest administrative body.
Mr Sahlas said Ablyazov should be released soon from the prison where he was detained.
Ablyazov's lawyers argued he was being pursued because of his activities as an opposition leader in autocratic Kazakhstan, and feared he would not get a fair trial in Russia or Ukraine. They also suspected he could be eventually transferred to Kazakhstan.
The banker fled Kazakhstan amid the nationalisation of BTA Bank. He was arrested in southern France in 2013 on embezzlement allegations. Both Russia and Ukraine have requested his extradition. France has no extradition agreement with Kazakhstan.