Oil prices tumbled more than $1 a barrel on Tuesday, after a strong rally in the previous session as worries about the global economic growth outweighed Saudi Arabia's pledge to deepen output cuts.

Brent crude futures were down $1.33, or 1.73%, to $75.38 a barrel by 0923 GMT. U.S. West Texas Intermediate crude fell $1.39, or 1.93%, to $70.76 a barrel.

Brent had gained as much as $2.60/bbl on Monday and WTI as much as $3.30 after Saudi Arabia, the world's top exporter, said at the weekend its output would drop by 1 million barrels per day (bpd) to 9 million bpd in July. The benchmarks pulled back, though, to more modest gains by the end of the day.

The U.S. services sector barely grew in May as new orders slowed, and market participants are waiting to see if the U.S. Federal Reserve will hike or hold interest rates in June.

Higher interest rates could curb energy demand.

Source : Reuters