PARIS—French bank Societe Generale said on Monday it would quit Russia and take a 3 billion euros ($3.3 billion) income hit from selling its Rosbank unit to Interros Capital, a firm linked to Russian oligarch Vladimir Potanin. Rosbank will rejoin the business empire of Potanin, the 61-year-old head of mining giant Norilsk Nickel, who has been sanctioned by Canada under western moves against Russia’s business and political elite over its invasion of Ukraine. He has not been sanctioned by the European Union or the United States. While financial terms of the deal were not announced, SocGen said Interros had agreed to pay off Rosbank’s subordinated debt. It said the hit to its capital buffers was just 20 basis points and it was sticking to its share buyback and dividend plans. SocGen had previously flagged the risk of a write-off on its 99 percent stake in Rosbank and investors welcomed the …