Codelco, the world's largest copper company, took a cautious view on the outlook for the red metal. It warned that it was unclear if US demand had bottomed out yet, said Europe was stagnant, and that the only bright spot was China.

Its guarded view comes as copper prices have surged in the first quarter to above $4,000 a tonne. Though less than half last year's record of $8,940, the price has shot up 30 per cent in the first quarter, outstripping even a rally in gold and hitting heights unimaginable a few months ago given the global economic gloom.