Oil firms were supposed to break-even on sale of petrol, diesel, LPG and kerosene if the price of the basket of crude India buys were to come down to USD 67 per barrel. However, with 20 per cent depreciation in value of rupee against the US dollar, the break-even point is now at USD 61 a barrel.

"The benefit of softening of the international oil prices has been partly offset by the recent depreciation of the rupee," a Petroleum Ministry official said.

Indian Oil, Hindustan Petroleum and Bharat Petroleum are losing about Rs 350 crore per day on fuel sales.

"The domestic retail prices at the time of revision in prices in June were equivalent to Indian basket of crude oil of USD 66 per barrel. With the recent depreciation of rupee against US dollar, the current retail prices now correspond to USD 61 per barrel of Indian basket of crude oil," he said.

The Indian basket of crude oil on Monday fell to USD 72.20 per barrel, the lowest level this year. It has averaged USD 79.70 a barrel in October.

The three firms are losing Rs 4.68 per litre on sales of petrol, Rs 11.48 on diesel, Rs 28.07 on kerosene and Rs 322.14 per LPG cylinder and are projected to lose Rs 1,62,158 crore on fuel sales this fiscal.

"International prices of crude oil and petroleum products are still higher than the prices at which current retail prices are fixed and so there is no valid reason for downward revision in retail prices," he said.

The official said the three fuel retailers were borrowing heavily for financing their working capital and capital expenditure requirements.

"The combined borrowings of the three, which stood at Rs 48,400 crore in March 2007 and Rs 66,900 crore in March 2008, has increased to Rs 93,500 crore as of August, 2008," he said.

The oil firms' credit limits have recently been enhanced by Rs 14,000 crore to enable them to meet their fund requirements till the end of October.

"The interest burden of the three companies during 2008-09 is expected to go up by Rs 4,200 crore compared to previous year due to increase in borrowings and higher rate of interest," he said.