Petrol price has been slashed by 32 paise per litre and diesel by 85 paise. The new rate came into effect midnight Friday night. Petrol will, now, cost 59 rupees 3 paise a litre in Delhi, 64 rupees 87 paise in Kolkata, 66 rupees 9 paise in Mumbai and 59 rupees 45 paise in Chennai.For diesel, the consumer will have to pay 44 rupees 18 paise in Delhi, 48 rupees 7 paise in Kolkata, 51 rupees 25 paise in Mumbai and 45 rupees 36 paise in Chennai.In a statement, Indian Oil Corporation said the decision has been taken in view of decrease in the prices of petrol and diesel in international market and changes in rupee-dollar exchange rate. This was the fourth reduction in rates in six weeks on the back of softening global oil prices.