U.S. crude settled down 5 percent at $48.87 a barrel on Friday as fears about the disruption of Middle East crude shipments from Yemen's conflict eased, and focus turned to the likelihood of an Iranian nuclear deal by next week that could put more supply on the market.
But prices were still headed for a second straight week of gains, reflecting the ground made by market bulls from six-year lows hit earlier this month.
The number of rigs drilling for oil in the United States declined by 12 this week to 813, the smallest decline since December, oil services firm Baker Hughes said in its closely watched survey on Friday.
That compares with declines of 41 and 56 rigs in the prior two weeks and is a sign the collapse in drilling over the past few months has slowed.
With the decline this week, the number of oil rigs has fallen for a record 16th week in a row to the lowest level since 2011, according to Baker Hughes data going back to 1987.