Oil prices advanced higher in early Asian trade Monday supported by a weaker dollar and diminished worries over Britain's possible exit from the European Union.
London Brent crude for August delivery was up 34 cents at $49.51 a barrel by 0235 GMT, after settling up $1.98, or 4.2 percent, at $49.17 on Friday.
On the New York Mercantile Exchange, light, sweet crude futures for delivery in July traded at $48.48 a barrel up $0.50 in the Globex electronic session. August Brent crude on London's ICE Futures exchange rose $0.42 to $49.59 a barrel.
According to Gao Jian, an energy analyst at SCI International, "The Brexit has been the single largest disturbance in the oil markets lately. Prices have been rising steadily as polls show the Remain camp now has the upper hand."
Brexit Vote Tied
Three opinion polls ahead of Thursday's vote showed the 'Remain' camp moving slightly ahead, although the overall picture remained one of an evenly split electorate.
Sterling surged 1.7 percent to $1.4603 as of 1:22 p.m. in Tokyo, after advancing 1.1 percent last Friday to complete its first weekly advance this month while the euro, Aussie and kiwi all strengthened at least 0.8 percent.
The won led gains in Asia, up 1 percent and the yen retreated 0.4 percent, its first decline in seven days and following a surge of 2.7 percent last week when it touched 103.55, the strongest in almost two years.
A global bond rally sent yields on government bonds to record lows from the U.K. to Germany, Japan and Australia.