Russia has opened a criminal investigation into the chief executive of potash producer Uralkali, Vladislav Baumgertner, and will request his extradition from Belarus, federal investigators said on Monday.

Belarus detained Baumgertner during a visit to Minsk in late August, about a month after Uralkali caused a row between Russia and Belarus when it unexpectedly pulled out of a sales cartel for fertiliser component potash with a partner in Belarus.

Russia's Investigative Committee said in a statement it had opened the investigation into Baumgertner on suspicion of abuse of power, the main charge he faces in Belarus.

Uralkali, which has previously denied Belarus' accusations against Baumgertner, declined to comment on the Investigative Committee's statement, which opens the door for the executive's return to Russia.

Belarussian President Alexander Lukashenko had said his country could hand over Baumgertner, 41, who is under house arrest in Minsk, as long as Russia took steps to prosecute him.

Baumgertner's arrest has put close but often tense relations between the two ex-Soviet allies under pressure, and speculation has mounted that Russian billionaire Suleiman Kerimov, Uralkali's main shareholder, may sell his $3.7 billion stake in a shake-up in its top management.