Rio Tinto Group has joined the ranks of multinationals shunning Russia following the country’s invasion of Ukraine, calling into question the fate of its aluminum joint venture with Moscow-based United Co Rusal International PJSC. “Rio Tinto is in the process of terminating all commercial relationships it has with any Russian business,” a spokesman for the global miner said in an e-mailed statement yesterday. The London-based company operates the Queensland Alumina Ltd joint venture with Rusal, which holds a 20 percent stake. While Rio is evaluating its options regarding the partnership...