Oil PSUs have increased aviation turbine fuel (ATF) prices by Rs 1600-1700 for the current month, Indian Oil Corporation (IOC) announced today.The fuel price increase would result in a cost increase of more than 4% for domestic airlines and more than 8% for international airlines.Aviation fuel prices are revised at the beginning of every month based on the average international price in the previous month.In Delhi, aviation fuel for domestic airlines will now cost Rs 39,767.75 rupees per kilolitre as against Rs 38,163.23 in a month back. Aviation fuel comprises 30-35% of airlines' total operational cost.