Inflation is expected to come down to the acceptable level of 5 to 5.5 per cent after four months due to good monsoons and the measures taken by the government and Reserve Bank, Prime Minister's Economic Advisory Council chairman C Rangarajan said on Monday.

"Inflation is likely to come down to 6 per cent in the next three to four months. Thereafter it can come down to 5-5.5 per cent depending upon the monsoons and other sectors," he told reporters in Delhi on the sidelines of an international tax conference.

Inflation will drop not only due to monetary measures announced by the Reserve Bank of India [Get Quote], but due to other factors as well, he said.

Also, it would be due to the base effect, as inflation was rising at a slower rate at this time last year. Despite all assumptions, it would come down, he said.

"Much will depend upon the monsoon. It is possible that inflation may go down to 5 to 5.5 per cent. At present, the expectations are that monsoons will be good," he said.

On the impact of fiscal measures taken by the government to curb inflation on tax collections, he said, "There will be, of course, some impact of fiscal measures. But I think it could be taken care of."

He also said the high oil crude oil prices, which have crossed $120 a barrel, could slow down India's GDP growth though it would not 'derail' the growth process.

"I think high oil prices will have its impact (on GDP growth). It could slow down growth," he said.

"In January, the council had projected the GDP growth at 8.5 per cent, but now I would say that it could be between 8 and 8.5 per cent," Rangarajan said.

According to advance estimates of the Central Statistical Organisation, the Indian economy is expected to register 8.9 per cent growth in 2007-08.

Rating agency ICRA has projected the Indian economy to grow at a lower rate of 7.8 per cent this fiscal.

Earlier, addressing the conference, Rangarajan said that there was a need to 'revisit' the tax structure on oil products in view of the rising international crude oil prices.

Later, when asked about the need, he said the comment was in view of the 'environmental aspect' as the taxes are imposed partly to curb oil consumption.

In 2007-08, crude oil and petroleum product imports, estimated at over $90 billion, accounted for 38 per cent of India's total imports.

With oil prices rising above $120 a barrel, the revenue losses of oil companies are expected to double to Rs 180,000 crore (Rs 1,800 billion) this year.

On review of duty structure on petroleum products, he said the council had earlier recommended an 'ad valorem' tax on oil products. Some of the suggestions have already been implemented by Finance Minister P Chidambaram in the Budget, he said.

Notably, the Indian basket of crude oil has touched an all-time high of $117.8 per barrel, an 87 per cent jump over the last fiscal's lowest price of $62.91 recorded on May 9, 2007.

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