Billionaire Alisher Usmanov has filed a lawsuit in a Moscow court to prevent TeliaSonera and Altimo from combining their stakes in Russia's third-largest mobile operator, MegaFon.
According to the web site of the Moscow Arbitration Court, the suit to nullify the deal was filed by Usmanov's vehicle Telekominvest against TeliaSonera and the Alfa Group unit on Tuesday.
Igor Tikhomirov, a spokesman for Usmanov, who holds a 31.1 percent stake in MegaFon, said: "Telekominvest has filed a lawsuit to the Moscow Arbitration Court in which it asks the court to prevent the creation of a joint venture between TeliaSonera and Altimo in Russian territory."
TeliaSonera and Altimo agreed to combine their stakes in MegaFon and Turkcell last year in a move to resolve a bitter dispute over ownership of the top Turkish operator and invited Usmanov to contribute his stake.
Usmanov rejected the invitation and said the merger would not contribute to the capitalization of MegaFon.
Altimo declined immediate comment on Wednesday.
Altimo holds 25.1 percent of the shares in MegaFon as well as 4.99 percent of Turkcell. TeliaSonera owns 37.3 percent of Turkcell and 43.8 percent of MegaFon.
TeliaSonera said it was not aware of any legal action and had no comment until it could confirm that such was the case.