Vekselberg was about to install Gilbertson as chairman of the world's biggest aluminum corporation when Vekselberg finished merging his aluminum company, Sual, with Rusal.
Vekselberg, 53, and Gilbertson, 67, have known each other since 2004, when Vekselberg convinced Gilbertson to run Sual, the aluminum producer Vekselberg cobbled together in the 1990s.