* Euro rises in relief rally after Portugal auction
* Spain, Italy debt auction, ECB on Thursday
* Markets hopeful of boost to euro zone lending fund (Adds quote, updates prices)
NEW YORK, Jan 12 (Reuters) - The euro rose against the dollar for a third straight day on Wednesday though gains were still seen as temporary after a Portuguese debt sale failed to stem fears over the funding prospects of peripheral euro zone countries.
Rising risk appetite boosted the euro, which climbed above $1.31 and broke above its 200-day moving average at $1.3071 on trading platform EBS after a 1.7 percent advance over three days.
Lisbon's debt auction saw healthy demand, with the average yield at the 10-year sale off, compared with a previous one in November, though 3-year bonds were sold at a significantly higher yield. For details see [
]."Markets are far from convinced that the crisis has begun, let alone ended," said Alan Wilde, head of fixed-income and currency at Baring Asset Management in London. Baring Asset Management oversees $50 billion in assets.
"Temporarily, the ECB has steadied markets using some judicious buying of sovereigns with the widest spreads, and the successful Portuguese auctions have resulted in a lift for the euro," said Wilde.
But analysts said the auction results would do little to change the view that the government in Lisbon will continue to struggle and may turn to the European Union and International Monetary Fund for a bailout.
"If we look at the 2014 issue, the yield was over 100 basis points higher than the last auction, which is not a good sign for Portugal's funding costs going forward," said Ronald Simpson, director of currency research at Action Economics in Tampa, Florida. "It keeps the door open (because) at some point they're going to need to formally ask for assistance."
Attention now turns to Spain and Italy, which will sell debt in auctions on Thursday that will also be watched for signs of contagion. Analysts expect the sales to go without a major hitch, but at elevated costs.
The euro <EUR=EBS> last traded 1.2 percent higher at $1.3133 on Wednesday, after rising as high as $1.3138 on EBS. At the session peak, the euro traded at the 50 percent Fibonacci retracement of the move from the Jan. 4 peak to the Jan. 10 low.
Analysts said further euro buying probably would not take the currency much further than $1.3150 in the near term. Near-term support lies at about $1.2794, the 61.8 percent Fibonacci retracement of its rally from June to November.
But a move above the 200-day SMA is seen as a first step toward improving sentiment toward the currency. The euro-dollar has now tested the 200-day simple moving average three times since Nov. 29, according to EBS data.
If it can hold gains above that level, technical analysts will view it as long-term support. Conversely if it falls below and continues to fall, that level will become long-term resistance.
RETESTING 4-MONTH LOW
Also bolstering the euro were comments from euro zone sources that finance ministers were likely to consider raising the effective lending capacity of the currency bloc's rescue fund next week in hopes of calming jittery markets. [
]This follows Japan's promise to support an upcoming bond sale by the fund, the European Financial Stability Facility.
Sentiment toward the euro zone single currency will remain subdued on persistent concerns that the debt financing problems affecting Portugal and Spain may spread, with some seeing Belgium in the firing line due to political instability.
Traders still expect the euro to retest its four-month low around $1.2860 set on Monday, with a break likely opening the door to a fall toward $1.2645 and $1.2590 in the coming weeks.
The European Central Bank meets on Thursday and investors will watch if the bank signals further steps to help ease pressure on peripheral bonds.
Against the yen, the euro was up 0.9 percent at 108.93 yen <EURJPY=EBS>. The dollar fell 0.3 percent to 82.96 yen <JPY=>.
The euro rose to a session high against the Swiss franc after the Swiss National Bank Vice Chairman Thomas Jordan said there are signs the Swiss economy will slow in 2011, though he still saw growth of about 1.5 percent <EURCHF=EBS>. The dollar fell to a session low against the franc <CHF=EBS>. [
]. (Reporting by Nick Olivari and Wanfeng Zhou; Additional reporting by Steven C Johnson; Editing by James Dalgleish)