Petrol and diesel prices were on Saturday hiked by 80 paise a litre each, taking the total increase in rates in the last 12 days to Rs 7.20 per litre.Petrol in Delhi will now cost Rs 102.61 per litre as against Rs 101.81 previously, while diesel rates have gone up from Rs 93.07 per litre to Rs 93.87, according to a price notification of state fuel retailers.Rates have been increased across the country and vary from state to state depending upon the incidence of local taxation.This is the 10th increase in prices since the ending of a four-and-half-month long hiatus in rate revision on March 22.In all, petrol prices have gone up by Rs 7.20 per litre.