Oil rose on Friday, notching its first monthly gain since August, as the market continued to balance risks to demand from the US budget standoff against concerns about disruption to Middle East supplies.
International benchmark Brent crude posted a 2.3 percent gain for November when fresh hostilities between Israel and Palestinian militants and unrest in Egypt stirred worries about global supplies, already affected by export disruptions in the North Sea and Nigeria.
Lingering concern about the struggling economy and its impact on fuel consumption weighed on prices at times during the month. Over the past week, the focus shifted to efforts by US lawmakers to reach a budget deal and avoid the so-called fiscal cliff -- $600 billion in automatic budget reductions and expiring tax cuts at the end of 2012 that could send the world's top oil consumer into recession.
Trade was choppy and light on Friday as the market remained gripped on the latest turns in the budget standoff.
Democrat President Barack Obama accused a "handful of Republicans" in the House of Representatives of trying to preserve tax cuts for the wealthy by holding up legislation to extend tax cuts for middle-class Americans. Speaker of the House John Boehner, a Republican, said the sides were at a stalemate.
Front-month Brent crude gained 47 cents on the day to settle at $111.23 a barrel, pushing over the 50-day moving average of $110.57 a barrel. The front month had closed October at $108.70 a barrel.
US crude gained 84 cents to settle at $88.91 a barrel, breaking through the 50-day moving average of $88.63 a barrel and bringing prices up 3.1 percent for the month. Buying picked up ahead of the settlement, hitting an intraday high of $88.99 a barrel.
"You don't want to be too short going into the weekend with all the geopolitical risk out there," said Phil Flynn, analyst at Price Futures Group in Chicago.
Tens of thousands of Egyptians protested against President Mohamed Mursi on Friday after an Islamist-led assembly raced through approval of a new constitution in a bid to end a crisis over the Islamist leader's newly expanded powers.
December RBOB gasoline prices edged down nearly 1 percent ahead of the contract's expiry on Friday, snapping two months of sharp spikes in the front-month contract before it headed off the board.
Low inventory levels in September and supply concerns near the October close due to disruptions caused by Hurricane Sandy helped drive the expiring contract higher during those months, and market players said those worries may have eased in November.
"(There) may have been long bets or supply hedges attributable to Hurricane Sandy disruption to New York Harbor facilities, which have mostly cleared, and the players decided they don't need barrels from futures contracts this month," said John Kilduff, partner at hedge fund Again Capital LLC in New York, speaking about December RBOB's dip at the expiry.
Traders were also factoring in data showing US consumer spending fell in October for the first time in five months as personal income remained unchanged, suggesting economic growth could be slower in the fourth quarter.
In a report on Thursday, U.S. GDP growth in July-September was revised up to 2.7 percent from an initial reading of 2.0 percent as restocking by businesses provided a big boost, but consumer and business spending were revised lower.