Oil prices rose on Tuesday as traders worried about the impact of a looming report on Iran's nuclear program, OPEC predicted stronger oil demand and as European stock markets rose.
Oil cartel OPEC predicted demand would rise by 5.3 percent to 2015, to 92.9 million barrels a day, compared with its previous 91.0 million barrels prediction.
New York's main contract, light sweet crude for delivery in December, climbed $1.28 one dollar to $96.52 a barrel.
In London Brent North Sea crude for December gained 44 cents to close at $115.00.
Political brinksmanship in Greece and Italy continued to play havoc with the European Union's push to get its comprehensive eurozone rescue plan into place, with both governments remaining on the rocks nearly two weeks after the plan was announced.
Oil futures rose in line with European stock markets, as investors hoped for a positive outcome to the eurozone debt crisis despite political theater in Italy and Greece.
Traders were also looking ahead to Wednesday, when a UN report is expected to provide new evidence that Iran is seeking the atomic bomb.
"Leaked information suggests that Iran is seen as geared to developing nuclear weapons, which could increase the risk of a military attack on Iran's nuclear facilities," analysts at Commerzbank said in a note on Tuesday.
"We believe this justifies a certain risk premium on the price of oil."
OPEC's forecast was also price-bullish, warning that uncertainty over energy and environmental policy was confusing the picture and could affect investment in exploration and production, tightening overall supplies.
On the other hand, the US Energy Information Administration, in its latest outlook, cut its forecast for global demand next year for the third month running, forecasting a 1.6 percent climb in total world consumption in 2012, to 89.62 million barrels a day.
The EIA said it expected the US oil price to stay around $100 a barrel next year, about the same as it had previously forecast.
Meanwhile Washington announced its five-year offshore exploration plan, promising oil companies more acreage in the Gulf of Mexico and in the Arctic off north Alaska -- though leases in the latter area would not be on sale before 2016.
But also clear in the program was that the US Atlantic and Pacific coast areas, as well as coastal Florida, would remain off-limits to oil drilling for the foreseeable future.