Oil prices rose for a second day in a row today, buoyed by greater investor appetite for riskier assets such as commodities and equities.

The gains came after polls showed a lower chance that Britain may vote to leave the European Union this week. 

August Brent crude futures were up 23 cents at $49.40 a barrel, on track for a 6% rise in two trading days. NYMEX crude for July delivery was up 42 cents at $48.40 a barrel. 

Campaigning for Britain's vote on EU membership resumed yesterdya after a three-day hiatus prompted by the killing of a pro-EU MP. 

Three opinion polls ahead of Thursday's vote showed the 'Remain' camp recovering some momentum, although the overall picture remained one of an evenly split electorate. 

Oil prices continued to recover despite data showing US energy firms adding oil rigs for a third week in a row, suggesting higher production to come.

Oil services firm Baker Hughes reported nine rig additions in the week to June 17. 

Aside from Brexit concerns, the market is likely to be caught in a range as any gains would likely be limited by the return of more shale drillers in the US analysts said. 

"Capping market gains at the moment is the potential for those very agile US producers to jump back into production should we see any further substantial rises," he said.