Crude prices slipped below 100 dollars on Thursday as investors remained nervous ahead of EU summit due on Friday on the European Central Bank's disappointing plan.
The ECB cut its benchmark interest rate by 25 basis points to 1 percent on Thursday, returning it to the record low level, in an effort to stop euro zone's potential recession. Besides, the bank decided to provide the region's cash-starved banks with loans for three years, trying to ease credit crunch.
ECB's decision came hours before the crucial EU summit, but failed to boost market sentiment, while Mario Draghi, the ECB president, said the bank would not consider further interest cuts and he remained cautious about more bond purchases, which disappointed the markets that had hoped more aggressive moves by ECB.
Besides, investors remained less confident in the summit, which was supposed to work out a decisive deal to address the ongoing debt crisis.
And the euro fell 0.5 percent against the dollar, resulting in a stronger dollar, which pressured the dollar-denominated crude.
On the economic front, U.S. initial jobless claims last week declined sharply by 23,000 to its lowest level since February, showing more momentum of recovery in the job markets.
Light, sweet crude for January delivery dropped 2.15 dollars, or 2.14 percent to settle at 98.34 dollars a barrel on the New York Mercantile Exchange. In London, Brent crude for January delivery also dropped about 2 percent and last traded around 107 dollars a barrel.