After showing a healthy expansion of 7.1 per cent in August, the growth in core infrastructure sector dropped to 4 per cent in September, making analysts wonder whether robust industrial recovery can be sustained.

The coal and cement which had led the chart in August by showing an impressive growth of 12.9 per cent and 17.6 per cent respectively, slipped to 6.5 per cent each in September, according to the official data released on Wednesday.

On year-on-year basis, the September growth this fiscal of the six sectors - cement, coal, steel, electricity, crude, oil and petroleum refinery products -- remained unchanged at four per cent.

The index of the core industries, which account for a quarter of the nation's industrial production, had helped the factory output reach a robust 10.4 per cent growth in August.

With infrastructure growth slipping again, it is a matter of debate if the August performance of the total industrial production can be repeated in September.

"I can say that IIP for September will not be in a double digit," CRISIL Principal Economist D K Joshi said. However, growth for the infrastructure industries for the first half of the current fiscal improved to five per cent from 3.4 per cent in April-September 2008-09.

"The figures reflect that investment and consumer demand is not growing," ICRIER Director Rajiv Kumar said.

Electricity generation grew by 7.5 per cent in September against 4.4 per cent in the same month last year, while Petroleum refinery products output expanded by 3.4 per cent in the month against 2.8 per cent in September 2008.

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