A crushing oil price rout extended into a sixth day, with U.S. crude nearly falling below $58 a barrel, as rising production, a strong dollar and a broad financial asset sell-off combined to weigh down the market.
The drubbing started last Friday and gathered steam this week, putting U.S. West Texas Intermediate crude on pace for its worst weekly performance in two years.
U.S. crude plunged to a seven-week low at $58.07 a barrel, before paring losses to end Friday's session down $1.95, or 3.2 percent, at $59.20.
Brent crude dropped $1.66, or 2.6 percent, to $63.15, after hitting a nine-week low at $61.77 by 2:28 p.m. ET.
For the week, U.S. crude was down nearly 9.6 percent, while Brent has fallen about 8 percent.
WTI broke below $59 a barrel after Baker Hughes reported the U.S. oil rig count rose by 26 rigs to 791, the highest total since April 2015.
The week's losses accelerated on Wednesday after government data showed weekly U.S. production jumping to a record 10.25 million barrels a day. Meanwhile, the nation's stockpiles of crude rose for a second straight week.
With American output on the rise, concerns are creeping into the market that OPEC's deal with Russia and other major producers to limit supply could come under pressure, said John Kilduff, founding partner at energy hedge fund Again Capital.
The head of Russian energy giant Gazprom Neft on Friday said producers could adjust their commitments under the deal as soon as next quarter, Reuters reported. Gazprom CEO Alexander Dyukov said he hoped producers would agree to raise output since the market has balanced after years of oversupply.
"It goes to the sense that folks are getting antsy about the production scheme holding together," he said.
Meanwhile, the dollar index is holding above 90 cents, putting pressure on commodities. A stronger greenback makes it more expensive for holders of other currencies to buy dollar-denominated commodities like oil.