Resignation comes a month after Nick Mather was handed a strong rebuke at the company’s annual meeting, when nearly half of shareholders voted against his reappointment to the board.
Both provinces displaced Western Australia from the first to the third place thanks partly to their rich mineral reserves, competitive tax regimes, efficient permitting procedures, and certainty surrounding environmental regulations.
The world's No.1 iron-ore producer recorded a net profit of $3.98 billion in 2016, a significant recovery from a loss of $12.13 billion it reported a year earlier.
A surge in commodity prices combined with its multibillion-dollar asset fire-sale has put the company in a position to pay big dividends and explore acquisitions.