The last time the government had hiked prices of octane and diesel was on June 20 this year. Price of octane was raised by Rs 2.50 per litre and diesel by Rs 2 per litre.

This was the fourth time that prices of diesel and octane were raised since the Congress-led UPA coalition government came to power in India in May last year.

Prices of octane and diesel vary in Delhi, Mumbai, Kolkata and Chennai because of local taxes and duties. Following the price increase in June this year, price of octane went up from Rs 37.99 to Rs 40.49 in Delhi, from Rs 43.23 to Rs 45.95 in Mumbai, from Rs 40.89 to Rs 43.51 in Kolkata and from Rs 41.25 to Rs 43.97 in Chennai.

The price of diesel went up from Rs 26.45 to Rs 28.45 in June this year in Delhi, from Rs 32.83 to Rs 35.22 in Mumbai, from Rs 28.72 to Rs 30.80 in Kolkata and from Rs 29.30 to Rs 31.52 in Chennai.

This price rise in June 2005 had come after a gap of seven months during which global oil prices surged by 20 percent and excise duty on octane went up. Despite the hike in prices of octane and diesel in June this year, four major Indian oil companies -- Indian Oil, Hindustan Petroleum Corporation Ltd, Bharat Petroleum Corporation Ltd and Indo-British Petroleum -- suffered a loss of Rs 1516 crore in July alone due to steep hike of six dollars a barrel in global crude prices.