It is official now. The reduction in the domestic prices of petrol and diesel has been less than the decline in the international prices of crude.

According to data prepared by the petroleum ministry, oil companies should have reduced the prices of petrol and diesel by Rs 1.58 a litre and 21 paise a litre, respectively, during April 1-15 in accordance with the international prices of crude.

However, the four public sector oil marketing companies -- Indian Oil Corporation Bharat Petroleum Corporation Ltd, Hindustan Petroleum Corporation Ltd and IBP -- gained Rs 48 crore (Rs 480 million) on the sale of petrol and Rs 31 crore (Rs 310 million) on diesel by not lowering their prices during the fortnight.

During the second fortnight of April, while the oil companies reduced the prices of petrol and diesel by Re 1 a litre, global crude prices warranted a Rs 4.60 a litre cut in the prices of petrol and a Rs 2.42 a litre cut for diesel.

The companies are expected to gain Rs 109 crore (Rs 1.09 billion) from the over-pricing of petrol and Rs 212 crore (Rs 2.12 billion) from diesel.

However, this is just one side of the story. The oil marketing companies also charged less and absorbed losses for the two fuels during February and March, when the international prices of crude were ruling high.

For instance, in the first fortnight of March, while petrol prices should have gone up by Rs 4.60 a litre and diesel prices by Rs 3.38 in keeping with international crude prices, the oil firms raised the prices of petrol by Rs 1.39 a litre and those of diesel by Rs 1.37.

Therefore, during March 1-15, the oil companies lost Rs 88 crore (Rs 880 million) on petrol sales and Rs 298 crore (Rs 2.98 billion) on diesel.

The corresponding figures for the second fortnight of March were Rs 75 crore (Rs 750 million) and Rs 296 crore (Rs 2.96 billion).

In 2003, the oil marketing companies have lost Rs 89 crore (Rs 890 million) on petrol sales and Rs 701 crore (Rs 7.01 billion) on diesel sales due to under-pricing.

In the Rajya Sabha on Tuesday, the government defended the decision to go slow on the reduction of domestic prices of petrol and diesel compared to international prices saying the oil marketing companies had spared the customers from a steep hike in prices prior to the Iraq war.