"Many of our members are still unclear whether they should invest on diesel technology or not in India as there is no clarity on how the fuel will be priced in future.
"This has resulted in more than Rs 3,000 crore (Rs 30 billion) of investment being held back," Society of Indian Automobile Manufacturers director general Vishnu Mathur said.
While he did not share the specific investments of each company, he said firms that have held back investing on diesel engine plants include Maruti Suzuki, Hyundai Motor India, Ford India, General Motors India and Tata Motors.
In November last year, Hyundai Motor India Ltd announced putting on hold its Rs 400-crore (Rs 4-billion) diesel engine plant which would have an installed capacity of 150,000 units per annum.
The plant was envisaged to manufacture three different engines of 1.1 litre, 1.4 litre and 1.6 litre capacities only for the domestic market.
Maruti Suzuki India, on the other, has been maintaining that without a clear-cut policy on
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