Oil prices rose slightly towards 50 dollars a barrel on Thursday, despite news of surging US crude inventories that indicated weak energy demand in the recession-hit US economy, dealers said.
Brent North Sea crude for delivery in June gained five cents to 49.86 dollars a barrel.
New York's main futures contract, light sweet crude for June, added 30 cents to 49.15 dollars a barrel.
The Department of Energy (DoE) said Wednesday that American crude oil stockpiles had surged 3.9 million barrels in the week ending April 17 -- marking the sixth weekly gain in a row.
Crude inventories in the United States are now about 17 percent above their level at the same stage last year, and remain at the highest level since September 1990.
"The market is still looking weak," said analyst Andrey Kryuchenkov at investment group VTB Capital in London.
"Once... fundamentals (of supply and demand) start appearing increasingly negative -- just like yesterday -- the market looks to equities" for investment instead.
European stock markets crept higher on Thursday as investors digested news that Swiss banking giant Credit Suisse returned to profit in the first three months of 2009 after two successive quarters of massive losses.
The bank said net profit hit 2.0 billion Swiss francs (1.32 billion euros, 1.71 billion dollars) in the first quarter, which helped calm fears about the financial crisis.
But Wall Street shares had spluttered Wednesday in a choppy session as disappointing results from Morgan Stanley reignited jitters about prospects for the bank sector and fears grew on General Motors' future.
The DoE added Wednesday that reserves of gasoline and distilled products, such as diesel and heating fuel, also increased, confounding analyst expectations of declines.
"Crude oil prices held up well against a report of increased inventories, and continue to hold up thus far today," analyst Brenda Sullivan at Sucden Financial Research said on Thursday.
Over the past four weeks, Americans consumed on average 18.5 million barrels a day of petroleum products, a decline of 6.5 percent from the same period a year earlier, despite the dramatic plunge in oil prices from peaks above 147 dollars a barrel in July 2008.
