Oil prices slipped on Wednesday after data showed a second consecutive weekly jump in U.S. crude oil stockpiles, with trading choppy as dealers tested the notion that last week's four-year low may have set a bottom.
Prices rose and fell several times, even after the U.S. Energy Information Administration said crude inventories rose by 7.11 million barrels, more than the 2.7 million-barrel increase analysts had expected.
"The large crude oil build is the dominant feature of the report, making it bearish overall," said John Kilduff, partner at Again Capital LLC in New York.
Crude settled down $1.97 at $80.52 a barrel, lowest since June 2012.
Brent has tumbled from $115 in June on abundant supply, OPEC's reluctance to curb output and concerns that slowing economic growth in Europe and China would dent oil demand.
Some traders have suggested that prices may be bottoming out due to growing expectations that a price near $80 a barrel could slow growth in production from the booming U.S. shale oil patch or Canada's costly oil sands reserves.
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Others remain anxious about the downside.
"Right now the markets have been trying to push up for two days and now it's coming back down, so we have to wonder if we're going to price some of those fears back in," said Gene McGillian, an analyst at Tradition Energy.
CNBC.com contributed to this report.