* Trichet gives no guidance on bond buying
* Talk of ECB bond buying helps lift euro
* U.S. jobless claims rise in latest week (Updates prices, adds comments)
By Gertrude Chavez-Dreyfuss
NEW YORK, Dec 2 (Reuters) - The euro gained in volatile trading on Thursday, boosted by reports the ECB was buying bonds, but uncertainty over the outlook for peripheral euro zone countries should keep the currency under pressure.
Reports the European Central Bank was buying Portuguese and Irish debt followed investor disappointment ECB President Jean-Claude Trichet did not announce a more aggressive policy response to ease the euro zone debt crisis.
While the euro's fundamentals have remained the same post-Trichet, most analysts said the common currency's 2-1/2 month low hit earlier this week would act as a strong support level for now. Traders are now looking at the euro's 100-day moving average at $1.3325 as the next resistance level.
In tandem with the euro's rise, the premium that investors demand to buy Portuguese and Irish debt over German benchmarks fell on Thursday, with traders saying the European Central Bank had been buying the two countries' bonds. That caused the euro to recover from losses triggered after Trichet's remarks.
"In times like this, we actually think the best thing to do is not to chase short-term moves," said Bob Sinche, global head of currency strategy at RBS in Stamford, Connecticut.
"Euro/dollar was overdone to the topside on quantitative easing part 2 and went overdone on the downside on fears of an imminent euro zone crisis. I think we have come back to the euro's fundamental valuation, which in our view, is actually $1.32-$1.33."
Sinche said he wouldn't be surprised if, depending on the outcome of the U.S. non-farm payrolls report on Friday, the euro ends the week "somewhere north of the 200-day moving average and somewhere south of the 100-day moving average."
The euro fell following Trichet's comments on disappointment the ECB made no new commitment to undertake a new bond-buying plan.
Instead the ECB extended nonstandard provisions, committing to provide unlimited one-week, one-month and three-month funding for vulnerable euro zone banks until at least April, a move viewed by the market as too soft.
PREVIOUS BOND BUYING
The euro rallied, however, on talk the ECB bought peripheral bonds. Market sources suggested the bank purchased more bonds than they did all of last week. The ECB had bought 1.348 billion euros in euro zone bonds last week, with total purchases at 67 billion euros since May, when the bond-buying program was launched.
In midday New York trading, the euro was up 0.6 percent at $1.3224, with session lows at $1.3060 in the wake of Trichet's remarks. Traders cited stops right above $1.3225.
Overall, the intraday bias in euro/dollar remains neutral for now as the currency consolidates from lows at $1.2969 earlier this week, traders said. Another rise cannot be ruled out, according to ActionForex.com analysts, at the hourly 55-day exponential moving average around $1.3279. But they said strong resistance is expected at $1.3447.
Some analysts were not surprised the ECB did not announce n any new bond buying program as many members of the bank have opposed such action.
"So unless the now highly politicized situation is resolved, the euro is likely to continue to be under pressure in the near term, which is our expectation because a lack of consensus in the ECB and EU would make credible and substantial responses hard to come by," said Aston Chan, portfolio manager at global macro hedge fund GLC in London. GLC has assets under management of around $1.2 billion.
The ECB has been under pressure to soothe market sentiment after a bailout plan announced for Ireland last month stoked speculation that other euro zone nations struggling to repay their debts may also seek help from the European community.
The dollar was down 0.6 percent against the yen at 84.20 , earlier weighed down by a rise in the latest U.S. weekly jobless claims. Robust U.S. data and higher U.S. bond yields have been supportive of the greenback of late. (Editing by Andrew Hay)