Oil prices fell as much as 4% on Thursday, breaking through a key support level, as rising U.S. crude stockpiles helped offset concerns about a supply crunch.
Crude futures declined despite a wave of geopolitical concerns, including political turmoil in Venezuela and the launch of new American measures aimed at driving Iran's crude exports to zero.
U.S. West Texas Intermediate crude settled $1.81 lower at $61.81 on Thursday, tumbling 2.8% to its weakest closing price since April 1. WTI plunged 4% to a session low at $60.95 earlier in the session.
"The $62 level is an important level. If you break through it you could trade down to $58 pretty quickly," said John Kilduff, founding partner at energy hedge fund Again Capital.
Brent crude oil futures, the international benchmark for oil prices, fell $1.43, or 2%, to $70.75 per barrel. Brent fell as low as $69.68 earlier in the session.
The drop was partly due to the overhang from Wednesday's weekly report on U.S. crude stockpiles, which showed inventories surging by 9.9 million barrels. The data also showed U.S. oil production ticking up to a record 12.3 million barrels per day.
U.s. crude stockpiles have risen in five of the last six weeks, helping to ease the market's concern that global oil supplies are getting tight.
"The market is a little bit spooked that we might have a repeat of last year, where there are all these bullish factors on the supply side globally, but U.S. shale [oil] is just this big behemoth in the background," said Tamar Essner, director of energy and utilities at Nasdaq Corporate Solutions.
Reports that Asian refineries are asking Saudi Arabia for more crude oil are also weighing on prices, said Kilduff. Any sign that the Saudis will answer those calls will push prices lower, he said.
The refiners are reportedly worried about supply shortages in light of U.S. sanctions on Iran and Venezuela.

Washington on Thursday stopped issuing waivers that allow several countries, including China and India, to purchase Iranian oil. The Trump administration restored sanctions on Iran's energy industry in November.
President Donald Trump is largely relying on Saudi Arabia to fill the gap left by Iranian supplies. Saudi Arabia has not explicitly committed to hiking output, but says it will respond to the market's needs.
"Saudi Arabia, the UAE, and Russia will likely fill the supply gap in the coming months, increasing the U.S. incentive to strictly enforce compliance and pressure Iran," Paul Sheldon, chief geopolitical adviser at S&P Global Platts Analytics said in an email briefing.
The U.S. sanctions will likely remove 700,000-800,000 bpd from the market, Helima Croft, head of global commodity strategy at RBC Capital Markets, told CNBC's "Worldwide Exchange" on Thursday.
Saudi Arabia, its fellow OPEC members, and other producers including Russia have been limiting supply since January. The so-called OPEC+ alliance meets at the end of next month to discuss whether to extend the six-month deal beyond June.

Meanwhile, street protests erupted in Venezuela this week after opposition leader Juan Guaido called on the military to abandon socialist strongman Nicolas Maduro.
Venezuela's oil production has plunged throughout the OPEC member's ongoing political and economic crises. The Trump administration slapped sanctions on Venezuelan oil giant PDVSA earlier this year in order to starve Maduro's regime of revenue and push him out of office.
"The White House will likely look to further erode the country's oil export revenue by compelling consuming countries like India to curb their Venezuelan purchases" if Maduro clings to power, Croft said in a research note.
Civil conflict also continues in OPEC-member Libya, where a battle between rival power centers threatens to disrupt the country's oil exports.
In Europe, Poland said it will release strategic oil supplies. Poland is one of several countries that suspended shipments from Russia after contaminated Russian crude was discovered in a major pipeline system.