Oil prices have fallen following a 2% rally on previous trading session, as commodity investors tried to sell out future adopting profit-taking positions.
Brent crude fell 20 cents at $49.05 a barrel, while the US benchmark West Texas Intermediate crude slipped 37 cents lower at $45.89 a barrel, Reuters reported.
The rally in crude prices was supported by an increase in gasoline prices in the US, as well as comments made by Russia that it was ready to discuss with OPEC and non-OPEC oil producers to discuss on oil market.
Crude oil sales in Iran are set to drop following a fall in purchases made by its main Asian customers.
The drop goes against the market expectations that exports in the country would increase significantly once a nuclear deal is in place by Tehran and six world powers on 14 July.
Investors are keenly watching for further signals for data to be released by the US Government on crude inventories this week.
According to some analysts, the data would show a rise in crude stocks, putting oil prices under pressure.
Crude inventories increased last week and gained 1.8 million barrels on average, a Reuters poll indicated on Monday.