New Delhi, Jul 26 (IANS): Diesel prices rose for the second straight day on Sunday, nearing Rs 82 per litre in the national capital.

Petrol prices, however, were unchanged for the 27th consecutive day across the four metros.

In Delhi, diesel was priced at Rs 81.94 a litre. With a 15-paise hike on Sunday, diesel is now Rs 1.51 costlier than petrol in the city.

After the hike, Diesel prices in Mumbai, Chennai and Kolkata were Rs 80.11, Rs 78.86, Rs 77.04 respectively, higher than Rs 79.97, Rs 78.73 and Rs 76.91 a litre on Saturday.

Unexpected rise in diesel prices despite slower demand has put the transport sector at a big disadvantage as rising fuel cost has further shrunk its margins. The price of diesel in the national capital has also made automobile companies concerned about the prospects of the sale of diesel-run cars in the country's largest car market.

Petrol prices, which were last hiked on June 29, again remained unchanged across the four metros.

In Mumbai, Chennai and Kolkata, petrol was sold at an unchanged price of Rs 87.19, Rs 83.63, Rs 82.10 per litre respectively.

Oil companies resumed the dynamic pricing system for daily revision of the two auto fuels from June 7 after keeping the price unchanged for around 82 days during the lockdown.