After two substantial hikes in transport fuels in May, state-owned oil marketing companies (OMCs) are likely to increase petrol and diesel rates this week.

The three state-run OMCs review prices of diesel and petrol every fortnight, depending on global oil prices and currency movements.

According to Indian Oil, it had to raise prices in May due to volatility in the rupee value and hardening of international motor spirit (MS) and diesel prices in the international market.

"Since the last price change, there has been a steep increase in international prices of both petrol and diesel. Rupee-dollar exchange rate has also depreciated quite significantly during this period," IOC said on May 15 when it hiked petrol by Rs.3.13 a litre and diesel by Rs.2.71 a litre, including state levies.

The rates were previously increased on May 1 by Rs.3.96 per litre for petrol and by Rs.2.37 a litre for diesel. The price of petrol per litre currently is Rs.66.29 in Delhi, Rs.73.76 in Kolkata, Rs.74.12 in Mumbai and Rs.69.45 in Chennai.

Diesel currently costs Rs.52.28 a litre in Delhi, Rs.56.85 in Kolkata, Rs.59.86 in Mumbai and Rs.55.74 in Chennai.

May saw the first hikes after a succession of cuts following a plunge in international crude oil prices in 2014 to around $43 per litre, that regained somewhat in 2015.

The Indian basket of crude oil cost $62.83 a barrel on the last trading day on Friday. A barrel equals 159 litres.