Following the recent spurt in oil prices to well over $50 a barrel, state-run Indian Oil Corp (IOC) on Sunday hiked prices of petrol by Rs 1.29 a litre, and of diesel by 97 paise, both at Delhi and effective from midnight, with corresponding increases in other states."The current level of international product prices of petrol and diesel and the INR-USD exchange rate warrant increase in selling price of petrol and diesel, the impact of which is being passed on to the consumers with this price revision," IOC said in a release here.Petrol per litre from Monday will cost Rs 70.60 in Delhi, Rs 73.13 in Kolkata, Rs 76.91 in Mumbai and Rs 70.07 in Chennai.Similarly, diesel will cost Rs 57.82 in Delhi, Rs 60.06 in Kolkata, Rs 63.61 in Mumbai and Rs 59.47 in Chennai.Rates were last hiked on December 16, petrol by Rs 2.21 a litre, and diesel by Rs 1.79 paise, both in Delhi, with corresponding changes in other states.With oil producers outside the Organisation of the Petroleum Exporting Countries (OPEC), led by Russia, agreeing to reduce output by 558,000 barrels per day (bpd) last month, the Indian basket of crude oils gained more than $3 a barrel over the weekend of December 11-12 even as global prices surged to an 18-month high.This came in the wake of the 13-nation OPEC cartel's November 30 decision to cut output by 1.2 million bpd for six months effective January 1.It is the first time since 2001 that OPEC and some of its rivals reached a deal to jointly reduce output in order to tackle the global oil glut.As per available data, the Indian basket, comprising 73 percent sour-grade Dubai and Oman crudes, and the balance in sweet-grade Brent, closed trade on Thursday at $54.54 for a barrel of 159 litres.