 BHP Group on Tuesday posted a 7 rise in fourth-quarter iron ore output, but warned the resurgence of COVID-19 outbreaks threatened the short-term demand outlook for its key commodities and widened its production guidance range for next year. Mining companies are banking on the recent uptick in industrial activity in China, the worlds top metals consumer, to support prices and insulate them from uncertainty over demand elsewhere, as global coronavirus cases continue to spike. The worlds biggest listed miner met guidance for its iron ore production of a record 67 million tonnes for the quarter, up 4, and 248 million tonnes for the financial year, reflecting strong demand from top consumer China. 