The head of the world’s biggest mining group has contradicted predictions of a sustained rebound in commodity prices as a result of a rapid global economic recovery, by warning that the upturn will be slow and protracted.

Marius Kloppers, chief executive of BHP Billiton, the Anglo-Australian group, said although he expected the world to undergo a period of “stabilisation” in the next three to six months, the medium-term outlook remained uncertain. “We do not expect a sharp rebound,” he said at a mining conference in Canberra on Wednesday.