LONDON (AFP) - Oil prices sank close to 35 dollars a barrel on Thursday after OPEC crude producers trimmed their demand forecasts for 2009 because of the global economic downturn. New York's main contract, light sweet crude for delivery in February, tumbled $1.84 to $35.44 on the New York Mercantile Exchange, after falling as low as 35.05. Brent North Sea crude for February was down 27 cents at $44.81 on London's InterContinental Exchange. The contract expires at the close. Prices had climbed in earlier trade on Thursday, recovering slightly after a mixed performance on Wednesday. But prices turned lower after OPEC cut its forecasts for global oil demand, predicting that demand would contract by a bigger-than-expected 0.2pc this year. "The depressed world economy is expected to have a large impact on oil demand this year," especially in industrialised countries, the Organization of Petroleum Exporting Countries wrote in its latest monthly report on Thursday. "The year 2009 started with a very depressed world economy which caused the year's oil demand forecast to show negative growth" of 0.18m barrels per day (bpd) or 0.2pc, the report said. In its previous monthly bulletin released in December, OPEC had pencilled in a contraction of 0.15 million bpd for 2009. "The considerable uncertainty about the course of the recovery implies the potential for further deterioration in world oil demand growth this year," the January report continued. Since September, OPEC has cut output by a total of 4.2 million barrels per day to try to combat falling crude prices. OPEC's decision last month to cut oil output by 2.2 million bpd has helped stem the slide in prices, the cartel added on Thursday. However, "achieving an acceptable level of stability will take time given the ongoing challenges facing the global economy." In 2008, global oil demand was estimated to have contracted by 0.1 million bpd, "the first decline in over two decades," OPEC added. The market saw choppy trade on Wednesday after fresh US data showed rising crude stockpiles, underlining weak demand in the world's largest energy consumer. The US Department of Energy revealed that crude reserves climbed 1.2 million barrels in the week ending January 9. Distillates, which include heating fuel and diesel, added 6.4 million barrels.