By Keith Wallis
SINGAPORE (Reuters) - Brent crude climbed above $58 a barrel on Thursday for the second straight session as speculators covered their positions ahead of the April contract's expiry, while a strengthening dollar and a build in U.S. crude stocks capped prices.
Geopolitical tensions in the Middle East and North Africa also supported crude futures.
Brent for April delivery was up 47 cents to $58.01 at 0746 GMT after gaining $1.15, or 2 percent, in the previous session in a rebound from a one-month low. The benchmark hit $58.25 a barrel earlier in the session.
West Texas Intermediate climbed 29 cents to $48.46, after closing the previous session down 12 cents.
The April contracts for Brent and WTI expire next week.
"When contracts expire there is more uncertainty and volatility associated with oil. For investors speculating, directionally WTI seems to be facing more pressure heading down. Brent will move upwards," said Victor Shum, vice president of IHS Energy in Singapore.
Brent's premium to U.S. crude widened to almost $10 a barrel on Thursday, after dropping below $8 on Tuesday, its narrowest in a month.
Bearish sentiment towards WTI caused by the build in U.S. crude oil stocks had helped to widen the spread, limiting the gains in WTI, said Yusuke Seta, a commodity sales manager at Tokyo's Newedge Japan.
U.S. crude inventories rose for the ninth straight week by 4.5 million barrels last week to 448.9 million, U.S. Department of Energy data showed.
That was the highest level at this time of year in more than 80 years.
"Oil inventories are expected to increase further," Seta said.
Any gains in prices could be short-lived as oil stocks are forecast to rise further due to refinery maintenance and the greenback could continue strengthening against the euro, said analysts.
Potential supply disruptions, including escalating violence in Libya where Islamist militants kidnapped nine foreign oilfield workers on March 6, were the main bullish factors to a strong Brent price, Shum said.
The euro slipped to a fresh 12-year low against the dollar on Thursday, while the dollar index also rose to hit 100.06 on Thursday for the first time since April 2003.
A strong greenback makes goods denominated in the dollar more expensive for holders of other currencies and limits their purchases for commodities and other assets.
(Editing by Tom Hogue and Prateek Chatterjee)
