Rio Tinto boss sees grey skies ahead Rio Tinto boss Sam Walsh. Picture: Marie Nirme Source: The Daily Telegraph RIO TINTO chief Sam Walsh has warned investors to brace for more volatility in the global economy and hinted at his support for the Federal Coalition's plan to cut the company tax rate. Mr Walsh called for more long-term policy stability from government as he announced net profit at the miner had fallen 71 per cent to $US1.72 billion ($1.9 billion) in the six months to June, compared with the same period a year earlier. Underlying earnings were down 18 per cent to $US4.23 billion - in line with analysts' expectations. Rio's bottom line was dragged down by $2.5 billion in one-off costs, most related currency exchange losses. The company also said it was abandoning plans to sell its struggling Pacific Aluminium division - which lost $US67 million during the period - saying securing a decent price "is not possible in the current environment." Speaking from London after the group published its results late today, Mr Walsh said he hoped Australia's federal election led to a political consensus to deliver long-term, stable policy settings. Asked if he thought Tony Abbott's plan to cut the company tax rate by 1.5 percentage points was a good idea, Mr Walsh replied: "International competitiveness is very, very, important. It's the same in every jurisdiction we operate. We are a business that makes long-term investments. We need as much certainty as we can get. We need stable policy settings. That is what it is all about. The company has slashed $1.5 billion from its cost base, including cutting 2200 jobs, since the end of June last year.