London - Oil prices fell on Friday on the back of a sharp rise in US crude stockpiles and after Saudi Arabia rejected proposed output cuts.
At around 14:30, US benchmark West Texas Intermediate for delivery in March fell 66 cents to $30.11 a barrel.
Brent North Sea crude for April delivery shed 46c to $33.82 a barrel compared with Thursday's close.
Crude futures ran out of steam on Thursday after the US Department of Energy said US commercial crude inventories rallied 2.1 million barrels last week to reach the highest level in more than eight decades.
The DoE also revealed sizeable increases in gasoline and other refined products.
An inventories rise typically suggests soft demand in the world's biggest oil consumer and is bad news for a market wallowing in excess supply.
This week's price rally also fizzled out after Saudi Foreign Minister Adel al-Jubeir rejected any reduction in his country's crude output.
"If other producers want to limit or agree to a freeze in terms of additional production, that may have an impact on the market, but Saudi Arabia is not prepared to cut production," Jubeir told AFP in an exclusive interview.
On Wednesday, WTI jumped more than seven percent while Brent added 5.6%, after Saudi Arabia and Russia, the two biggest producers in the world, agreed to limit their pumping - but only if others followed suit.
This sparked hopes the market would stabilise after prices sank to near 13-year lows last week.
However, speaking to AFP over the telephone from Sydney, CMC Markets chief market strategist Michael McCarthy said more market volatility can be expected.
"I don't think anybody seriously believes that anything useful is going to come out of these discussions between OPEC and Russia," he said.
Saudi Arabia is regarded as the de facto leader of OPEC.
BMI Research also said any output freeze was unlikely.
"Given weak forecast output growth amongst committed countries, the agreement will remove few, if any, barrels from the market," a commentary said.
"Countries with strong forecast production growth this year - including Iran - are unlikely to submit to the freeze."
Saudi Arabia and other OPEC producers have refused to reduce output in an attempt to drive less competitive players, in particular US shale oil producers, out of the market.