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BHP CEO step downs

BHP Billiton's chief executive Marius Kloppers will retire from the role in May.

The announcement came as the global resources giant posted a 58 per cent fall in first half profit to $US4.24 billion ($A4.14 billion) due to lower commodity prices and a weak US dollar.

Mr Kloppers is to be replaced by the 56-year-old head of BHP's non-ferrous business, Andrew Mackenzie.

BHP's net profit in the six months to December 31 was down from $US9.94 billion ($A9.70 billion) in the previous corresponding period.

The result included $US1.4 billion ($A1.37 billion) in one-off costs from asset sales.

Profit excluding one-off items was $US5.7 billion ($A5.56 billion) in the six months to December, down 43 per cent from $US9.94 billion ($A9.70 billion) for the December 2011 half, due to falls in iron ore and other commodity prices in 2012.

Analysts had expected a net profit excluding one-offs of $US5.69 billion ($A5.55 billion).

Underlying earnings before interest and tax (EBIT) of $US9.8 billion ($A9.57 billion) was down 38 per cent from $US15.7 billion ($A15.32 billion), but slightly higher than analyst expectations.

BHP Billiton took $US3 billion ($A2.93 billion) of impairments during the half, including $US865 million ($A844.27 million) on its Australian nickel business, $US1.53 billion ($A1.49 billion) on its Worsley alumina refinery in Western Australia and $US655 million ($A639.31 million) from a capital projects review.

It said that, notwithstanding short-term volatility, a modest improvement in the global economy was anticipated over the next 12 months.

The company said it was optimistic about the Chinese government's policies supporting stable growth, while the US was benefiting from relatively low energy costs.

Eurozone markets had stabilised following the European Central Bank's commitment to provide more financial support.

Despite the current high iron ore prices, BHP said it believed the addition of low-cost supply in many markets and a maturity in China's infrastructure-led growth would dampen pricing for iron ore and metallurgical coal.

However, copper supply growth in the very near term was expected to result in a more balanced market.

BHP lifted its interim dividend by 3.6 per cent to 57 US cents.