* Euro up 0.3 pct at $1.3187 EUR=
* Euro gets boost after Spanish, French bond auction results
* Markets hope ECB will expand bond purchase programme
* Disappointment could see euro head back below $1.30
(Adds quotes, updates prices)
By Tamawa Desai
LONDON, Dec 2 (Reuters) - The euro held firm on Thursday after rising the previous day as investors waited to see if the European Central Bank would take more steps to calm euro debt concerns, but could fall again if the central bank disappoints.
The euro posted its biggest one-day rise in more than a month on Wednesday on speculation the ECB would massively step up its bond purchases, after the single currency struck 11-week lows against the dollar.
All eyes were on the ECB, which is expected to keep unlimited liquidity operations in place for longer [ID:nLDE6B01V3] but hold off from more radical measures [ID:nLDE6B00SW].
The ECB will announce the outcome of its policy meeting at 1245 GMT, followed by ECB President Jean-Claude Trichet's news conference at 1330 GMT.
"The focus is on whether Trichet will announce a numerical target for bond purchases. If he keeps to saying they are ready to buy more bonds but without a numerical target, the markets will be disappointed and turn negative on the euro," said Roberto Mialich, currency strategist at Unicredit in Milan.
Furthermore, traders may take advantage of such a situation to dump euro/dollar long positions ahead of key U.S. payroll data due out on Friday.
"The (U.S.) ADP numbers raised expectations Friday's jobs report will not be so bad, making players adverse to holding excessive euro/dollar longs," Mialich said.
By 1001 GMT, the euro was up 0.3 percent on the day at $1.3187 EUR=. It had jumped more than 1 percent the previous day after hitting an 11-week low at $1.2969 on Tuesday.
Bids from Asian and Middle East accounts seen around $1.3130 supported the downside, traders said.
It rose to the day's high of $1.3197 as stop-loss orders were triggered above $1.3180 and after the results of Spanish and French government bond auctions showed they were relatively well received. [ID:nMDT009552] [ID:nTAR01130]
Offers were seen around $1.3180/1.3200, traders said.
The euro has fluctuated on either side of its 200-day moving average at $1.3123 and analysts said disappointment from the ECB could see it resume the fall it began in early November and head back below $1.30.
Interactive timeline on euro zone debt crisis in 2010:
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"If (the ECB) can get a temporary positive spin on things we will get a chance to sell at $1.33 and if they don't we will have to crush the euro back through $1.30," a London-based trader said.
"Either way, it's a sell," he said, adding the ECB at this point can do "nothing more than keep the wolves at bay for a bit longer."
The euro was earlier supported after a U.S. official told Reuters Washington would support boosting an EU rescue facility via IMF funds, although a Treasury Department spokesman later said an "extra commitment is not something we're discussing right now." [ID:nWAT014766].
The U.S. dollar was little changed against the yen at 84.12 yen JPY=, not far from a two-month high of 84.41 yen hit on Monday. Robust U.S. data and higher U.S. bond yields may support the greenback, traders said. (Additional reporting by Naomi Tajitsu, editing by Catherine Evans)