By Lewa Pardomuan SINGAPORE (Reuters) - Gold slipped almost 1 percent on Tuesday after rallying to a one-week high the previous day, as a weaker euro and falling crude oil prices prompted investors to book profits. Platinum also fell from a one-week high to track gold prices, but the metal has bounced almost 30 percent since tumbling to a five-year low around $730 an ounce in late October, partly driven by purchases by Japanese investors. Gold was trading at $828.60 an ounce, down $5.59 from late trade on Monday, when it rose as high as $845.55 in volatile trade. U.S. markets reopen on Tuesday after Martin Luther King holiday. "The U.S. dollar might pop up due to optimism surrounding the swearing in of U.S. President-elect Barack Obama later today," said Pradeep Unni, an analyst atRichcomm Global Services. "This might curtail any recovery in gold." "Oil has certainly been instrumental in dragging gold lower. However the dollar's strength is the key factor," he said. Barack Obama takes over as U.S. President on Tuesday with hopes riding high he can conjure up a rescue that will jolt the world's biggest economy back to life and contain the financial crisis ravaging global markets. The euro extended falls following a ratings downgrade of Spain by Standard & Poor's, grim economic forecasts from the European Commission and a worsening outlook for the financial sector after Royal Bank of Scotland unveiled its biggest loss in UK corporate history. The euro fell to $1.3012 after touching a six-week low of $1.2988 on trading platform EBS. Oil extended losses below $34 a barrel on Tuesday, after Russia and Ukraine signed a gas deal that would help secure supplies to Europe, while no improvement was in sight for oil demand. Bullion dropped to a one-month trough around $801 last week on a falling euro and stock markets, but the decline also spurred buying from jewellers ahead of the Lunar New Year next week. "It could have gotten a bit positive after gold neared the $850 regions but it looks like we are back down again on a weaker euro and pound," said Adrian Koh, analyst at Phillip Futures in Singapore, referring to a high seen last week. "It's pretty much currency driven today. I think yesterday's rise was a bit of follow through from the sharp rally in the previous day. And traders as well as investors probably stopped short at key resistance levels." Falling stock markets could weigh on gold, with the Nikkei and Asian stocks outside outside Japan both sliding more than 2 percent. Platinum was trading at $943.00 an ounce, down $5.50 from Monday's late trade. The metal has attracted buying from bargain hunting in Asia, with prices now trading more than 50 percent below a record above $2,200 struck last March. "Platinum is a bit more positive than gold, possibly because it did dip to almost par levels as compared to gold and industry players were buying on its relative cheapness," said Koh of Phillip Futures. New York gold futures fell $10.3 an ounce to $829.6 in electronic trade. | 
