Oil prices slipped Tuesday as buyers remained hesitant amid worries about progress in the eurozone and global demand at large. West Texas Intermediate for November delivery lost 59 cents to $91.89 a barrel in New York trade. In London, Brent North Sea crude for November gave up 62 cents to end at $111.57 a barrel. \"It was a relatively calm session in petroleum markets until prices came under some pressure late in the day.... Risk for oil prices to the downside outweighs the upside,\" said BMO Capital markets. \"Crude oil prices continue to remain on a consolidation mode, as the market looks overbought while persistent concerns about the eurozone\'s economic stability continue to weigh on market sentiment,\" said Sucden Financial Research analyst Myrto Sokou. Oil watchers were following events in Iran, whose currency slid between two and six percent in trading on Tuesday after losing 17 percent the day before, according to money changers in Tehran and an exchange tracking website. Iraq announced it plans to export 2.9 million barrels of oil per day in 2013 and hopes to increase production to 3.4 million bpd by the end of this year, a high-ranking official said on Tuesday. \"Next year the plan is 2.9 million bpd of exports,\" Thamir Ghadhban, Prime Minister Nuri al-Maliki\'s main advisor, said on the sidelines of the third Iraq Mega Projects conference held in Dubai.