U.S. crude oil futures fell for a fourth session in five on Tuesday as fears of a liquidity crunch in China and the potential withdrawal of stimulus in the United States spurred worries about demand in the world's top oil consumers.
 

U.S. crude for August delivery dropped 32 cents to $94.86 a barrel by 0101 GMT. The contract rebounded by $1.49 on Monday after a three-day slide that slashed prices by almost $5.

Brent crude eased 25 cents to $100.91 a barrel.

(Read More: Oil Heading Lower After 'Black Thursday')
 

The oil benchmark hit a three-week low of $99.67 in the previous session before finishing above $101.

China's central bank has engineered a tightening of cash in money markets as it tries to rein in excessive credit growth, especially in the lightly regulated "shadow banking" sector, seeing interest rates spike to 25 percent or higher for some deals late last week.

(Read More: China's Central Bank Plays Hardball—Will It Backfire?)

Two top officials of the Federal Reserve downplayed the notion of an imminent end to monetary stimulus and said the recent sell-off in financial markets was not yet cause for concern.

Major oil Canadian pipelines that move almost 1 million barrels per day of Alberta oil sands crude, much of it bound for the United States, remained shut on Monday after a spill on a smaller line was discovered on the weekend.

South Korea has pledged to the United States that it will cut imports of Iranian crude by 15 percent in the next six months to secure its next waiver to U.S. sanctions targeting Iran's nuclear program.