New Delhi: Indian Oil Corp said it would raise the retail price of petrol by 5.5 and that of diesel by 6.6 from Sunday, as global prices of the two fuels have risen since the last revision. Retail prices of petrol will be raised by Rs3.18 a litre and that of diesel by Rs3.09 a litre, it said in a statement on Saturday. Prices may vary in different cities due to local taxes and levies.