A flicker of doubt over the growth of the Chinese economy wiped £9 billion off the value of London’s largest miners yesterday and sent commodities to a five-year low.

Investors ditched mining stocks after the Chinese finance minister played down the prospect of economic stimulus, despite the lowering of growth forecasts. The Communist party is targeting 7.5 per cent growth this year and analysts fear that any deviation from that will have a drastic impact on the price of raw materials such as iron ore and copper.

The downbeat message was compounded by a prediction from the China Iron and