* Euro STOXX 50 down 1.1 pct, FTSEurofirst down 0.9 pct
* ECB's lack of details on fresh stimulus unnerves investors
* Italian, Spanish, Greek banks lead declines
By Francesco Canepa
LONDON, Dec 4 (Reuters) - Euro zone shares fell on Thursday after the European Central Bank cut growth and inflation forecasts and said it would make a decision on further stimulus early next year.
That disappointed some traders who had bet that Thursday's meeting would bring details of additional measures, possibly a U.S.-style government bond-buying scheme, seen as strongly supportive for the equity market.
ECB President Mario Draghi said the bank would reassess the impact of its recent policy measures early in 2015, though not necessarily in January, and take further action -- including such quantitative easing -- if needed.
"Investors were hoping for more substance on sovereign bond purchases, but Draghi hasn't given investors anything that is really new," said John Smith, senior fund manager at Brown Shipley.
At 1441 GMT, the euro zone Euro STOXX 50 <.STOXX 50E> index was down 1.1 percent at 3,211.92 points. The pan-European FTSEurofirst 300, which had been hovering just below a seven-year high, was down 0.9 percent at 1,388.07 points.
The ECB slashed its forecasts for growth and inflation over the next two years, saying the outlook had deteriorated since September when its previous staff predictions were published.
Banks in deflation-struck Italy, Spain and Greece, which own sizeable holdings of sovereign bonds and depend on the health of their domestic economies for their profits, led the declines.
National Bank of Greece, Italy's Monte Paschi and Spain's Bankia fell between 3.6 percent and 4 percent.
Italy's FTSE MIB index and Spain's Ibex were down 1.5 percent and 1.2 percent, respectively.
While a perceived lack of detail caused investors to cash in recent stock market gains, many still believed the ECB would announce sovereign bond purchases next year. Draghi said technical preparations for further stimulus measures were being stepped up.
"Draghi sent the clear message today that markets should expect more from the ECB early next year without actually announcing anything particularly new," Luke Bartholomew, investment manager at Aberdeen, said. (Additional reporting by Atul Prakash in London and Blaise Robinson in Paris; Editing by Catherine Evans)