WASHINGTON, D.C. (AP).- Billionaire Russian investor Vladimir Potanin announced a $5 million gift Thursday to the Kennedy Center for the Performing Arts to mark its 40th anniversary and support its programs. The gift, a first from Russia to the Washington center, includes additional funding from Potanin’s foundation to renovate an Opera House lounge at the center. It will be renamed the Russian Lounge and redecorated to feature Russian culture when it reopens in late 2012. Potanin, 50, is a founder of Interros Company and the biggest shareholder in the world’s largest nickel producer, Norilsk Nickel. For years, he has been locked in a dispute with rival Oleg Deripaska over control of the mining giant. Engaging with the Kennedy Center is a “natural expansion” of his foundation’s philanthropic activities in Russia, Potanin said in a written statement ahead of the gift