* Spot gold breaks above 200-day moving average * China Nov silver imports down 43 pct on year * Eyes on ECB's offer of three-year loans to banks * Coming up: U.S. existing home sales, Nov; 1500 GMT (Adds details; updates prices) By Rujun Shen SINGAPORE, Dec 21 (Reuters) - Gold rose to a one-week high on Wednesday, extending gains from the previous session, as upbeat economic data from the United States and Germany boosted market sentiment and a weaker dollar lent support. The euro edged higher, riding on a sharp rise in German business sentiment and strong demand for Spanish debt, with investors watching the European Central Bank's first offer of three-year loans to banks that many hope will help the region's banks lower their funding costs. On the chart, spot gold pierced above the 200-day moving average, seen as a key support since 2008 until a week earlier when prices plunged. "The rebound in gold today is related to the currency market," said Dick Poon, manager of precious metals at Heraeus in Hong Kong. "But we don't see much fresh buying from investors as the year end nears." Poon said gold could rise towards $1,650 by the end of the year, but the thinning trading volume could stir up great volatility in prices. Spot gold rose as much as 0.9 percent to a one-week high of $1,628.3 before easing slightly to $1,627.89 an ounce by 0714 GMT. It rallied 1.3 percent in the previous session. U.S. gold gained 0.8 percent to $1,630.20. Holdings of SPDR Gold Trust, the world's biggest gold-backed exchange-traded fund, remained unchanged for a third consecutive session at $1,279.975 tonnes by Dec 20. "What surprised me is holdings of gold ETFs are still holding up despite the recent sell-off, which is a good sign," said Dominic Schnider, head of commodity research at UBS Wealth Management. But gold is unlikely to visit its historical high any time soon as uncertainties around the euro zone debt crisis and global growth have created a liquidity crunch that hurts gold's sentiment as much as it hits riskier assets. "Gold is not the asset of choice on a search for liquidity. It gives you comfort against currency risks, inflation, sovereign debt problems, but not liquidity crunch," Schnider said. Spot platinum hit a one-week high of $1,441.50 and eased to $1,440, up 0.8 percent from the previous close. Spot palladium also rose 0.8 percent to $628. Barclays Capital suggested that in the first quarter investors build length in markets where fundamentals are most supportive, including copper, platinum group metals and gold. "Across the metals sector and arguably for commodities as a whole, supply constraints look tightest in the PGMs," it said in a research note, adding that the deteriorating output in South Africa and Russian palladium stockpiles widely believed to be near exhaustion would trigger a drop in platinum and palladium supply next year. Spot silver edged up 0.4 percent to $29.63 an ounce. China's silver imports in November posted a decline of 43 percent from a year earlier to 232,053 kilograms, down for a third consecutive month, the official customs data showed. Precious metals prices 0714 GMT Metal Last Change Pct chg YTD pct chg Volume Spot Gold 1627.89 13.60 +0.84 14.68 Spot Silver 29.63 0.12 +0.41 -3.99 Spot Platinum 1440.00 12.01 +0.84 -18.53 Spot Palladium 628.00 5.09 +0.82 -21.45 TOCOM Gold 4068.00 59.00 +1.47 9.09 42411 TOCOM Platinum 3631.00 50.00 +1.40 -22.68 11174 TOCOM Silver 73.40 1.60 +2.23 -9.38 352 TOCOM Palladium 1576.00 34.00 +2.20 -24.85 103 COMEX GOLD FEB2 1630.20 12.60 +0.78 14.69 13151 COMEX SILVER MAR2 29.66 0.12 +0.42 -4.14 1736 Euro/Dollar 1.3117 Dollar/Yen 77.74 TOCOM prices in yen per gram. Spot prices in $ per ounce. COMEX gold and silver contracts show the most active months

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