In further evidence that oil supply is proving difficult to suppress, the latest rig data from Baker Hughes indicates a swelling on Friday.
The weekly tally rose to 617 in service from 609 a week before.
That marked an eighth weekly increase in a row. The total active US rig count, which includes oil and natural-gas rigs, also rose by 12 to 768, according to Baker Hughes.
On Wednesday oil prices began a two-day slide after shock EIA data showed US inventories jumped in the most recent week and heightened worries over whether OPEC and Russia will keep in tact their pledge to cut the supply glut in order to boost oil prices.
The West Texas Intermediate, the US oil price benchmark, was down 1.6% to $48.47 on Friday.
Story by ProactiveInvestors