Speaking at Rio’s annual general meeting in London overnight, du Plessis said problems in overseas markets had not yet been fixed.

“Over the past five years we have experienced market volatility unlike anything we have ever seen before,” he said.

“While the outlook is now brighter in some parts of the world, we believe that volatility looks set to remain in the short to medium term as a number of structural deficiencies remain unresolved.”

Du Plessis said tensions remained in Europe and the pace of reform was slow.

In the US, the unwinding of quantitative easing represented uncharted territory.

Looking to Asia, he said China’s strength was a big positive but there were still questions over its long-term direction.

“While the fundamental drivers of the Chinese economy remain intact, we can expect some variability in the near term as authorities endeavour to steer the economy along a more sustainable and steady path of growth,” he said.

“There is no question, however, that the Chinese leadership remains committed to pursuing economic reform, which offers potential benefits for the global economy in the long term, even if there is some variability along the way.”

Du Plessis said 2013 saw Rio continue with the strategy that had worked well for it in the past, investing in long-life and low-cost operations in the most active industry sectors.

He said the focus for 2014 would be to continue to pay down debt and strengthen the balance sheet.

Speaking alongside du Plessis, Rio CEO Sam Walsh said 2013 had seen the company post production records in bauxite, thermal coal and iron ore.

He said the company’s key projects included the iron ore expansions in the Pilbara and a move underground at the Argyle diamond mine in Western Australia.

Operations at Oyu Tolgoi in Mongolia and the expansion of the Kestrel coal mine in Queensland were also focus areas.

Alongside those expansions Walsh said retaining the focus on productivity would help keep Rio competitive.

“Increasing productivity helps us reduce costs, to work more efficiently and to improve performance, which in turn provides us with options to invest in the long-term future of our business,” he said.

Yesterday Rio set records for March-quarter iron ore production, shipping and rail, saying the performance set new benchmarks for the operations.

Rio Tinto shares were last trading steady at $A63.35.