Belarusian authorities plan to launch a criminal investigation of the major shareholder of Russia's Uralkali potash-producing company.
Belarus's Investigative Committee spokesman said that one of Russia's richest citizens, Suleiman Kerimov, who owns 25 percent of Uralkali shares, is suspected of illegal activities.
The committee gave no specific details on the potential charges.
On August 26, Belarusian authorities detained Uralkali General-Director Vladislav Baumgertner in Minsk.
The move sparked tensions between Belarus and Russia.
Baumgernter was chairman of the Belarusian Potash Company (BKK), a now defunct joint venture between Uralkali and a Belarusian potash firm, Belaruskali.
His announcement in July that Uralkali was leaving BKK led to a steep drop in the commodity's price, affecting the Belarusian economy.
The Russian Embassy in Minsk says that its representatives are due to meet Baumgertner on August 29.
Based on reporting by Interfax and ITAR-TASS