Petrol and diesel prices were on Thursday hiked by 80 paise a litre each, taking the total increase in rates in the last 10 days to Rs 6.40 per litre. Petrol in Delhi will now cost Rs 101.81 per litre as against Rs 101.01 previously while diesel rates have gone up from Rs 92.27 per litre to Rs 93.07, 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 ninth increase in prices since the ending of a four-and-half-month long hiatus in rate revision on March 22. In all, petrol and diesel prices have gone up by Rs 6.40 per litre each.