New Delhi, July 12 : Diesel prices across the metro cities increased on Sunday, after remaining unchanged for four consecutive days. With a 16 paise hike in diesel price in New Delhi, the gap between diesel and petrol prices widened in the national capital. Last month, an unprecedented development, diesel prices overtook that of petrol in the national capital. Diesel was priced at Rs 80.94 per litre on Sunday in the capital, higher than the previous level of Rs 80.78 a litre. Similarly, in Mumbai, Chennai and Kolkata, prices of the fuel increased to Rs 79.17, Rs 78.01, and Rs 76.05 per litre respectively from Rs 79.05, Rs 77.91 and Rs 75.89 on Saturday. Petrol prices, however, remained unchanged across the major cities. In Delhi, Mumbai, Chennai and Kolkata, it was priced at Rs 80.43, Rs 87.19, Rs 83.63, and 82.10 a litre respectively, same as on Saturday. /IANS