He has been given more time to make a firm offer or walk away from a deal to buy out minority shareholders in Vedanta Resources for 778 million pounds ($1 billion).
Two large shareholders in Canada's Ecobalt Solutions Inc are calling for a change in senior management or the launch of a sales process, saying ongoing mine development delays are wasting a windfall from high battery sector demand.
Billionaire Anil Agarwal in July said he planned to offer around $1 billion to take London-listed Vedanta Resources Plc private, a move that has rekindled speculation his ultimate aim is a deal with miner Anglo-American.
Lundin Mining Corp launched a hostile takeover bid for fellow Canadian base metals miner Nevsun Resources Ltd on Thursday, saying it had failed to convince Nevsun's board to agree to a friendly deal over the past nine months.