LONDON (AFP) - Oil prices fell on Tuesday as OPEC decided at a meeting against changing the cartels official crude output levels, in a widely-expected move. New Yorks main futures contract, light sweet crude for delivery in February, dropped 32 cents to 73.40 dollars a barrel. Brent North Sea crude for February lost 35 cents to 72.64 dollars in afternoon London trading. The Organization of Petroleum Exporting Countries (OPEC) held its crude output quotas unchanged at its meeting in Angola on Tuesday, warning of lingering weakness in the world economy. The economic recovery has gathered pace, the groups president, Angolan Oil Minister Jose Botelho de Vasconcelos, said at the start of the meeting. The market remains well supplied. Prices have moved up to more comfortable levels, he said as he welcomed ministers to the first OPEC meeting hosted by Angola. However, the fragility remains in the market and we should not forget the detrimental volatility we experienced last year, Vasconcelos added. The cartels most influential member, Saudi Oil Minister Ali al-Naimi said crude price levels were perfect. Everybody is happy, he told reporters. Were happy with it ... because the investor is happy. Tuesdays meeting caps a year of recovery for oil prices, which have more than doubled since the cartel set strict quota cuts in the depths of the economic crisis a year ago. OPEC had last week slightly upgraded its forecast for world oil demand growth next year but said usage in advanced economies would contract again. The cartel said demand would grow by 0.82 million barrels per day (bpd) or 0.9 percent to average 85.13 million bpd, up slightly from its previous forecast for an increase of 0.75 million bpd. But growth would be driven by developing countries, with demand in industrialised or OECD (Organisation for Economic Co-operation and Development) nations continuing to contract, the cartel said. OECD oil demand was set to contract 0.28 percent in 2010 after falling by a record 3.9 percent in 2009. Last year was one of the worst years, with global demand estimated to have contracted by 1.39 million bpd or 1.6 percent to 84.31 million bpd, OPEC said last week.