Mikhail Prokhorov's suit, filed with the Moscow Arbitration Court, was also against United Press, the publisher of The Moscow Times, an English language newspaper distributed for free in the Russian capital.
In an interview with The Moscow Times on June 11, Potanin reportedly accused Prokhorov of failing to observe agreements during procedures to sell a blocking stake in metals giant Norilsk Nickel. The two businessmen have only recently completed the division of their joint assets - the process lasted about a year.
A court representative told RIA Novosti that the lawsuit, filed on July 21, could be adopted for consideration within five days.
It has been known since mid-June that Prokhorov's lawyers were preparing the lawsuit.
Prokhorov's representatives said they would submit to the court copies of documents refuting Potanin's accusations.
Prokhorov and Potanin co-own Russia's largest gold producer Polyus Zoloto, holding 30% each. They are both on the board of Norilsk Nickel.
Norilsk Nickel accounts for over 20% of global nickel output, more than 10% of cobalt production and 3% of copper.
The company's share on the Russian nickel market stands at around 96%. It accounts for 55% of domestic nickel production and produces 95% of Russia's cobalt.
