BHP Billiton is defying suggestions that the bulk of its cost cutting is done, unveiling new plans to remove a further $2 billion in capital spending and costs by 2017.
The global miner is also undertaking a major shake-up of its management ranks, appointing new heads for its important copper and coal divisions, and a new company secretary.
BHP has increased its target of annual productivity gains by $500 million to $US4 billion ($A4.33 billion) by 2017.
Investors welcomed the news, with BHP shares gaining $1.20, or 3.8 per cent, to $32.90, amid strong gains for all iron ore miners after interest rate cuts in China.
BHP chief executive Andrew Mackenzie said the proposed demerger of selected unwanted assets - including aluminium, manganese and some nickel and coal projects - would help drive the productivity gains.
They would deliver a "step change" improvement in BHP's performance that would allow it to bring on new production at lower costs without hurting volume growth, he said.
The productivity gains are expected to include a reduction in cash costs of $US2.6 billion a year.
Meanwhile, BHP plans to cut capital expenditure and exploration costs from $US14.8 billion to $14.2 billion this financial year and to $US13 billion in 2015/16.
BHP is upping the stakes in its efforts to lift production, profits and dividends despite cutting costs, with productivity gains a major driver of its higher $10.4 billion profit for 2013/14.
Many analysts argue the easy gains on cost cutting have been achieved, with BHP facing a drop in profits this year amid falls in the price of major commodities including iron ore, copper, coal and oil.
Details of the new productivity target came as BHP announced a management shakeup, which will involve current marketing head Mike Henry becoming president of BHP's coal assets, swapping roles with current coal chief Dean Dalla Valle.
Aluminium boss Daniel Malchuk has taken over as president of copper, which BHP is banking on as a key future growth division along with petroleum now that the iron ore price boom of recent years is over.
The miner has also recruited Commonwealth Bank company secretary Margaret Taylor to perform that role at BHP, replacing Jane McAloon.
All of Monday's announcements showed BHP trying to stay ahead of what was a bear market in iron ore and oil, IG market strategist Evan Lucas said.
"They want to continue to maintain margins there as strong as they can, they have talked about getting iron ore operational costs to $US20 a tonne in the next two years," he said.
"There are issues around coal and copper, they are feeling the feeling heat in those two divisions so have made structural changes at the top.
"We've seen Glencore, Vale and Rio Tinto move (on costs) and it is all about trying to reduce costs as much as they can and keep margins as strong as possible while they ride out the downturn in the market."