Crude tumbled to multi-week lows on Tuesday, as a deal averting any imminent U.S. attack on Syria calmed fears of a disruption to Middle East oil supplies, and after output resumed at a large oilfield in western Libya.
U.S. air strikes on Syria now look unlikely after the pact to remove Syria's chemical weapons, although the United States, Britain and France have warned President Bashar al-Assad of consequences if he fails to comply.
Oil supplies from Libya, hit this year by unrest and strikes, are set to recover after the government in Tripoli agreed a deal with protesters in the country's west to allow pumping to resume from one major oilfield.
Investors are also wary over the market outlook ahead of a meeting of the U.S. central bank, which is likely to signal tighter monetary policy and could strengthen the dollar.
Brent crude for delivery in November was down more than $2, trading near $108 a barrel as it hit a new one-month low.
Brent has lost more than 6 percent since hitting a six-month peak of $117.34 in late August when a U.S. military strike against Syria appeared imminent.
U.S. crude for October delivery settled down $1.17 at $105.42 a barrel, its weakest since September 3.
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