Oil prices edged up in early trading on Monday as output declines in Nigeria and worries about political instability in Venezuela tightened the market. The increase came despite rising OPEC output and a stronger dollar that capped gains. International Brent crude futures were trading at around 48 dollars per barrel, up about 0.6 percent, from their last settlement.

U.S. West Texas Intermediate WTI crude futures were up nearly 0.5 percent to trade at around 47 dollars a barrel. Analysts said the main contributor to the increase was falling supplies from producers such as Nigeria, and Venezuela due to political uncertainties. Crude production in the US has fallen as well as the sector suffers a wave of debt-fuelled bankruptcies.