Anglo American is sounding out potential investors for its Brazilian ore assets as it prepares a detailed response to Xstrata's £40bn merger proposal and accelerates the search for a new chairman.

The UK-based miner has held informal discussions with Gulf Industrial Investment Company, the Bahrain iron oxide pellet producer, and Sojitz, the Japanese conglomerate, about taking a stake of up to 30 per cent in MMX Minas-Rio, the Brazilian iron ore producer it acquired last year for £3.5bn.