LONDON, May 17: World oil prices rallied on Thursday as the market focused on problems at US refineries ahead of the high-demand season for motor fuel, and unrest in crude producer Nigeria, traders said.Crude futures had fallen on Wednesday after a US government report showed that American energy inventories had jumped by more than expected last week.

On Thursday, the price of Brent North Sea crude for July delivery jumped 1.24 cents to $69.21 a barrel in electronic deals.

New York's main oil futures contract, light sweet crude for delivery in June, advanced 84 cents to $63.38 per barrel in floor trading.

“Crude futures were higher - on the back of refinery closures, (which are) reducing gasoline supplies ahead of the summer driving season in the US,” said Sucden analyst Michael Davies in London.

The US Department of Energy said on Wednesday that gasoline (petrol) reserves rose 1.7 million barrels to 195.2m in the week ending May 11, above forecasts for a rise of 1 million barrels.

The gain followed an increase of 400,000 barrels the preceding week after steady falls for three months.

But news of recent US refinery glitches and shutdowns offset the increase in gasoline inventories, putting upward pressure on prices on Thursday, said Victor Shum, senior principal at Purvin and Gertz.

“The market is responding to refinery glitches. A couple of weeks of inventories build doesn't turn the market around.

—AFP