U.S. oil prices closed at the lowest level of 2013, after falling below $92 a barrel intraday Tuesday.
Brent crude is down nearly $2, trading below $113 a barrel, poised for the lowest settlement price since Jan. 29.
Here's what traders say is contributing to the selloff:
- Italy's election stalemate has escalated worries over the eurozone debt crisis and fuel demand
- Iran's talks with Western nations over its nuclear program have reduced the geopolitical risk premium in the oil markets
- Refineries resuming operations after planned maintenance or shutdowns has caused a big slide in refined fuels, dragging down overall oil market.
Gasoline futures are down 2.5 percent, also at their lowest levels in a month. Prices were pressured after Motiva Enterprises announced earlier Tuesday it is restarting operations at its gasoline-making unit in Port Arthur, TX. Motiva is joint venture between Royal Dutch Shell and Saudi Aramco.
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—By CNBC's Sharon Epperson; Follow her on Twitter: @sharon_epperson