* Euro seen likely to struggle after fall
* Sovereign debt woes haunt
* Dollar may gain on U.S. retail sales data
* Aussie rises after softer China CPI
By Hideyuki Sano
TOKYO, Feb 15 (Reuters) - The euro edged higher on Tuesday but faced headwinds in moving further away from a three-week low hit a day earlier when reports about ailing lender WestLB triggered another outbreak of worries on euro zone debt and banking problems.
Market players said the euro could slip back if upcoming U.S. data, including retail sales figures later in the day, paints an improving picture of the economy, which could push up U.S. interest rates further to the detriment of the euro.
"The dollar is likely to be bought back more. Investors have come to think that the Fed will not extend its quantitative easing beyond June, and markets will try to bet on an eventual rate hike by the Fed for now," said Etsuko Yamashita, chief economist at Sumitomo Mitsui Banking Corp.
The euro ticked up in Asia as traders tried to take out stop-loss orders around $1.3510-20, but lacked the momentum to go further.
In late Asian trade, it traded at $1.3515 <EUR=>, about 0.2 percent higher than late U.S. levels. It hit a three-week low of $1.3428 on Monday, when reports that rescue plans for WestLB were under threat triggered selling in the currency. [
]Talk of Asian central bank bids means immediate support for the single currency lies under $1.3450 and below that, key support now stands at $1.3360, the 50 percent retracement of a January to February rally.
But many traders expect the currency to struggle to gain traction amid the rekindled worries about the currency bloc's debt and banking problems.
Peripheral euro zone yield spreads have been widening in the past week on uncertainty over a rescue package for the region, and there was some disappointment after a meeting of European finance ministers on Monday.
The finance ministers agreed that a permanent rescue mechanism to be set up from 2013 would total 500 billion euros, but there was no agreement over how to beef up its existing rescue fund. [
]While policymakers have said they will hammer out a deal by March, analysts noted that there are some political events that could shake investor confidence on the euro in coming days.
They said a German local election on Feb. 20 could make Berlin reluctant to dish out aid to indebted countries.
Ireland's main opposition party -- slated to win a Feb. 25 poll -- has warned that it could unilaterally restructure bank debt, possibly imposing losses on senior bond holders, if it wins power this month.
"I suspect the market is starting to worry about sovereign issues. Euro long positions still remain to be unwound. The euro could fall to around $1.32-33," said Minori Uchida, senior analyst at the Bank of Tokyo-Mitsubishi UFJ.
The yield differential is also turning less favourable for the euro.
Two-year German bonds yielded 0.54 percentage point more than U.S. Treasuries -- the narrowest yield spread in nearly a month and sharply below a two-year high of 0.82 percentage point hit last last month.
SPREAD SHRINK
The spread shrank largely because U.S. yields jumped this month and two-year U.S. yields <US2YT=RR> are near eight-month highs.
Traders think a strong reading in U.S. retail sales due at 1330 GMT could fuel a rise in U.S. yields, thereby boosting the dollar's rally. Retail sales, which have been a bright spot in the economy, are expected to show a 0.6 percent rise in January from the previous month.
"The greenback may regain its footing over the next 24 hours of trading as the economic docket is expected to reinforce an improved outlook for future growth," said David Song, currency analyst at DailyFX.
"As market participants expect retail sales to increase for the seventh consecutive month in January, the expansion in private sector activity is likely to reinforce an enhanced outlook for the world's largest economy as household spending remains one of the leading drivers of growth."
Against the yen, the dollar gained 0.2 percent to 83.50 yen <JPY=>, edging close to a three-week high of 83.68 yen set on Friday.
The Bank of Japan kept rates on hold at the end of its two-day policy meeting as widely expected. [
]The Australian dollar rose 0.10 percent to $1.0037 <AUD=D4>. It was helped by China's consumer price index that came in at 4.9 percent, below market expectations of 5.3 percent, though it was exactly the same as a whispered number that swirled through markets yesterday.
"The data probably slightly eases expectations of immediate tightening, although in the overall scheme of things, this doesn't change the fact that China is still in a tightening phase," said SMBC's Yamashita. (Additional reporting by Ian Chua in Sydney; Editing by Edwina Gibbs and Joseph Radford)