"Improved perceptions of the macroeconomic environment, as the Fed pushed back its guidance for the timing of the first hike in federal funds rate target to at least 2014, have helped to support some commodities," said Barclays Capital analyst Sudakshina Unnikrishnan. "Further, China's December trade data continue to paint a picture of robust commodity demand, coming in stronger than markets had been expecting." In reaction to the Fed pledge, the euro has surged to one-month highs against the dollar, despite Greece's ongoing struggle to agree a writedown on its huge debts with its creditors. Some markets trimmed their gains late on Friday after US fourth-quarter economic growth fell short of market expectations. The weak greenback makes dollar-priced commodities cheaper for holders of stronger currencies, and therefore tends to stimulate demand and support higher price levels. OIL: World oil prices gained ground on the Fed news and as traders eyed ongoing geopolitical concerns over key crude producer Iran. The market benefited from the Federal Reserve's extension of the timeframe of its ultra-loose monetary policy to bolster growth. The Fed vowed to keep interest rates at "exceptionally low levels" at least until late 2014, extending its forecast from the previously stated mid-2013. Traders also speculated that the central bank could also decide to implement another round of stimulus in the form of quantitative easing (QE). Crude futures trimmed gains late on Friday after US fourth-quarter economic growth underwhelmed investors. The United States economy -- a leading consumer of oil -- grew by 2.8 percent in the fourth quarter, the Commerce Department said Friday. That dashed expectations for a pickup to 3.2 percent as consumer spending did not rise as much as expected, and followed the third quarter's tepid 1.8 percent expansion. "Crude oil prices have slipped back from their highs after US GDP numbers came in slightly lower than expected," said CMC Markets analyst Michael Hewson on Friday. "They still look set to finish the week higher to post their first weekly gains since the beginning of January, underpinned by Iranian threats to stop exports to the European Union." Traders kept an eye on the tense situation between oil-producer Iran and the West over Tehran's suspected nuclear weapons programme, which has triggered tough sanctions from the US and Europe. European Union foreign ministers have agreed a ban on Iranian oil imports and a phase-out of existing contracts up to July 1 to pressure Tehran to end its controversial nuclear programme. They also froze the assets of the country's central bank while ensuring legitimate trade under strict conditions. In a retaliatory move, Iran's parliament is expected to consider next week a bill to ban oil exports to Europe immediately before the embargo comes into force, according to media reports. The Islamic republic, which is already under four rounds of United Nations sanctions, vehemently denies its nuclear programme masks an atomic weapons drive as the West alleges, and insists it is for civilian purposes only. By late Friday on London's Intercontinental Exchange, Brent North Sea crude for delivery in March climbed to $111.30 a barrel from $110.05 the previous week. On the New York Mercantile Exchange, West Texas Intermediate (WTI) or light sweet crude for March rose to $99.89 from $98.21 for the February contract a week earlier. BASE METALS: Base or industrial metals forged ahead. "With the dollar under pressure, we are seeing 'risk on' trades seep into a number of commodity complexes and base metals should be a prime beneficiary in this regard," said analyst Edward Meir at brokerage INTL FCStone. "In addition, Wednesday's Fed statement should provide additional staying power for a stronger euro." By late Friday on the London Metal Exchange, copper for delivery in three months jumped to $8,577 a tonne from $8,225 the previous week. Three-month aluminium rose to $2,263 a tonne from $2,207. Three-month lead increased to $2,307 a tonne from $2,177. Three-month tin rallied to $24,500 a tonne from $21,800. Three-month zinc gained to $2,162 a tonne from $2,014. Three-month nickel advanced to $21,698 a tonne from $20,450. PRECIOUS METALS: Gold prices soared Thursday to the highest level in almost seven weeks as the dollar weakened, while silver, palladium and platinum scored multi-month high points. Gold hit $1,730.85 an ounce -- which was the highest level since December 8 but still far below the record peak of $1,921.15 struck on September 6. "With the US Federal pledging to keep interest rates in check until late 2014 -- gold soared," said Ross Norman, boss of British-based bullion broker Sharps Pixley. "Although there was heavy speculative buying, anxious investors joined the fray who are concerned by currency depreciation as global central banks use easy monetary policies to flood markets with cash." Gold had surged by $50, or about 3.0 percent in value, within two hours of Wednesday's Fed announcement. And the precious metal enjoyed its biggest one-day surge in four months, according to analysts. By late Friday on the London Bullion Market, gold rose to $1,726 an ounce from $1,653 the previous week. Silver gained to $33.48 an ounce from $30.36. On the London Platinum and Palladium Market, platinum increased to $1,608 an ounce from $1,517. Palladium climbed to $684 an ounce from $669. COCOA: The market surged to the highest levels since mid-November on fears over dry weather in Ivory Coast, which is the world's biggest producer of the commodity that is mostly used to make chocolate. "The weather in Ivory Coast is currently giving cause for concern, as unusually strong dry winds are hampering the development of the beans and deliveries are below last year's levels as the harvest gets underway," said Commerzbank analyst Carsten Fritsch. By Friday on LIFFE, London's futures exchange, cocoa for delivery in March rose to £1,583 a tonne from £1,527 a week earlier. In New York on the NYBOT-ICE, cocoa for March jumped to $2,454 a tonne from $2,320. COFFEE: Prices fell in nervous trade, bucking the positive trend in most other markets. By Friday on LIFFE, Robusta for delivery in March eased to $1,869 a tonne from $1,904 a week earlier. On NYBOT-ICE, Arabica for March dipped to 218.60 US cents a pound from 225.80 cents. SUGAR: Prices soared again to their highest levels for two months after the Fed pledge on low interest rates. By Friday on LIFFE, the price of a tonne of white sugar for March increased to $653 from $649.70. On NYBOT-ICE, the price of unrefined sugar for delivery in March slipped to 24.82 US cents a pound from 24.86 cents a week earlier. RUBBER: Prices rose due to tight supplies and positive investor sentiment because of Thailand's plan to support the rubber market. The Malaysian Rubber Board's benchmark SMR20 rose to 378.15 US cents a kilo from 367.20 cents the previous week.