LONDON - World oil prices rose this week as traders balanced positive global economic data against an improving supply picture.Elsewhere on commodity markets, sugar futures sank to fresh multi-year lows on prospects of a plentiful harvest. Raw material prices moved also on news that the World Bank had upgraded its 2014 forecast for global economic growth, suggesting potential improvement in demand.The World Bank said that both high-income and developing countries appeared to be "finally turning the corner five years after the global financial crisis". Global growth was estimated to hit 3.2 percent this year, accelerating from a 2.4 percent annual pace in 2013, the Bank said.OIL: Brent crude prices hit a two-month low Friday on oversupply concerns but ended the week higher overall as positive economic growth data indicated firmer demand.Brent North Sea crude for March delivery slid to $105.44 a barrel -- the lowest level since the end of 2013.The prospect of more supplies from Libya and Iran has weighed on sentiment this week."The expectation that supply from Libya and Iran could soon return to the market should initially continue to put selling pressure on Brent," said analysts at Commerzbank.At the same time, however, various upbeat global economic data releases have stoked hopes of strengthening global energy demand.Oil sank Monday on news that a landmark deal with world powers to curb parts of Iran's disputed nuclear programme, in exchange for sanctions relief, will take effect from January 20.Adding to downward pressure, Libya is widely expected to continue to recover lost production."Brent has (been)... torn between positive global economic data and an improving supply outlook from Northern Africa and the Middle East," said analyst Lucy Sidebotham at Inenco consultants.Added to the supply picture, the United States is also expected to ramp up production this year.On Thursday, oil cartel OPEC nudged up its world oil demand growth forecasts for 2013 and 2014, citing positive developments in Europe and North America.For 2013, the 12-member Organization of Petroleum Exporting Countries estimated demand at 89.86 million barrels per day (mbd), up 0.94 mbd from demand in 2012. In its previous monthly report in December, growth had been forecast at 0.87 mbd.The revision was helped by the US economic recovery and hikes in industrial and transportation fuel consumption there, OPEC said in its monthly report. Oil demand also started picking up in Europe at the end of 2013.OPEC added that demand for its oil was expected to fall in 2014 as the supply from non-members increased by an estimated 1.27 million bpd over 2013 to an average of 55.38 billion bpd.Non-OPEC supply growth was revised higher and mainly came from the United States and Canada."In 2014, the market will be caught in the crossfire of strong growth in US oil supply on the one hand and supply risk allied to OPEC supply management on the other," concluded BNP Paribas analysts in a research note."This is likely to result in another year of sideways movement in prices."By Friday on London's Intercontinental Exchange, Brent North Sea crude for delivery in March stood at $106.73 a barrel compared with $106.33 for the expired February contract a week earlier.On the New York Mercantile Exchange, West Texas Intermediate or light sweet crude for February grew to $94.29 a barrel from $92.27.PRECIOUS METALS: Gold prices advanced this week. The market lacks any firm direction and inspiration seems in short supply," said analysts at traders Triland Metals.By late Friday on the London Bullion Market, the price of gold rose to $1,250 an ounce from $1,244.25 a week earlier.Silver climbed to $20.01 an ounce from $19.80. On the London Platinum and Palladium Market, platinum increased to $1,447 an ounce from $1,425.Palladium advanced to $747 an ounce from $737.BASE METALS: Base or industrial metals prices mostly rose across the board on a tightening of supplies."The situation has tightened on many metals markets recently, partly due to supply and partly due to demand," said analysts at Commerzbank.By Friday on the London Metal Exchange, copper for delivery in three months dipped to $7,302.25 a tonne from $7,306 a week earlier. Three-month aluminium grew to $1,808 a tonne from $1,768. Three-month lead gained to $2,191 a tonne from $2,131.Three-month tin climbed to $22,301 a tonne from $21,950.Three-month nickel advanced to $14,560 a tonne from $13,752.Three-month zinc increased to $2,066 a tonne from $2,035.75.COFFEE: Coffee futures stabilised, supported by worries about the impact of dry weather on key producer Brazil."Worries about forecasts calling for unfavourable hot and dry weather in Brazil helped to underpin coffee futures, as did uncertainty surrounding the size of the country's upcoming coffee crop," said industry publication The Public Ledger.By Friday on the ICE Futures US exchange, Arabica for delivery in March eased to 117.95 US cents a pound from 118.75 cents a week earlier.On LIFFE, Robusta for March climbed to $1,725 a tonne from $1,714.SUGAR: The sugar market plummeted to its lowest levels in more than three and a half years, as sentiment was plagued by abundant supplies.Sugar dived on Thursday to $413.20 in London -- a level last seen in April 2009. New York prices hit 15.10 US cents, which was last witnessed in June 2010."Sugar values plunged... as speculators and funds added to short positions," said Sucden analyst Nick Penney."It seems the sugar market is all 'doom and gloom' at the moment, at least for producers who see their future crops diminish in value and for traders long of physical inventory and unable to place their sugar despite the sharp drop in prices."By Friday on LIFFE, the price of a tonne of white sugar for March slid to $418.10 from $424.90 a week earlier.On New York's ICE Futures US exchange, the price of unrefined sugar for delivery in March eased to 15.49 US cents a pound from 15.50.COCOA: Futures bounded higher on keen demand in Europe and North America, traders said.By Friday on LIFFE, London's futures exchange, cocoa for delivery in March climbed to £1,756 a tonne from £1,726 a week earlier.On ICE Futures US, cocoa for March increased to $2,740 a tonne from $2,697.