Anglo American is starting a formal process to sell its coal assets and explore options for its nickel operations after fending off a takeover threat from bigger rival BHP Group, CEO Duncan Wanblad said on Thursday. The Anglo CEO faces pressure from investors to boost the company’s value by improving operational efficiencies and speeding up the sale of assets after rejecting three takeover proposals from the world No. 1 miner, which on Wednesday said it had no choice but to walk out.