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Brent crude surged to a six-month high on Wednesday as western countries prepared to attack Syria, raising concerns over the security of oil supplies across West Asia, which pumps a third of the world's oil.
The US and its allies are readying for air strikes against the forces of President Bashar al-Assad, blamed for poison gas attacks last week. But the timing of any action was unclear.
A prolonged outage at several Libyan oilfields also underpinned prices, with Brent gaining four per cent and the US benchmark three per cent so far this week.
Brent was at $115.83, up $1.47 at 1214 GMT after earlier reaching a six-month high of $117.34 a barrel. US crude rose $1.45 to $110.46, after hitting an intra-day peak of $112.24 - its highest since May 2011.
