BHP shares had closed 0.42% lower at A$42.97 ($28.17) in Australia. "Anglo need to come out and explain to us how they're going to make this business more valuable," said George Cheveley, portfolio manager at Ninety-One. "You've got the largest mining company (making an) approach, it's a credible approach. You might argue the structure is wrong, and they might be able to change that," he added. Anglo, which rejected BHP's bid on Friday as opportunistic and significantly undervaluing the miner and its future prospects, will hold its AGM from 1000 GMT on Tuesday in London. But while shareholders would be keen to hear details of its response, restrictions in the UK Takeover Code mean executives are unlikely to be able to discuss plans beyond a repeat of the rejection, a source familiar with the matter said. In February, Anglo began a strategic review of its assets in response to a 94% fall in annual profit and a series of writedowns caused by lower commodity demand.