World stocks slipped on Wednesday as investors cautiously awaited the outcome of a Federal

RELATED ARTICLES Asian shares, euro slip on eurozone fears ECB move on Greek banks hits euro confidence Yahoo CEO out, investor Loeb gets board seats

Reserve meeting which could offer further stimulus for the ailing U.S. economy, while ongoing uncertainty about Greece's debt crisis pressured the euro.

The Federal Open Market Committee, the Fed's policymaking arm, is expected to end its two-day policy meeting on Wednesday with a decision to stock up on longer-term Treasury debt to push longer-term interest rates lower in a move dubbed "Operation Twist."

The Fed will issue a statement at about 2:15 p.m. EDT (1815 GMT).

It is unclear, however, how effective such new measures would be in bolstering U.S. growth, given that economic growth is slowing despite the central bank's $600 billion bond buying program that ended in June.

"Operation Twist is unconventional and the best they could offer," said Peter Cardillo, chief market economist at Rockwell Global Capital in New York. "But what will this do in terms of economic growth? I suspect very little.

"I think the Fed will satisfy the market, but since we are in a short-term overbought situation, even if the Fed doesn't disappoint, we might see a short-term pullback."

The MSCI world equity index was down 0.7 percent on the day, though still more than 3.0 percent above its one-year low set earlier in September.

U.S. stocks were mixed. The Dow Jones industrial average was down 20.55 points, or 0.18 percent, at 11,388.11.

The Standard & Poor's 500 Index was down 3.10 points, or 0.26 percent, at 1,198.99. The Nasdaq Composite Index was up 8.02 points, or 0.31 percent, at 2,598.26.

European stocks fell 1.5 percent while emerging stocks lost 0.9 percent.

Persistent fears of a possible Greek debt default weighed on investor sentiment, with Athens and international lenders yet to reach a deal to allow the next tranche of bailout funds to be paid.

The Greek government will make announcements later on Wednesday on the austerity measures it is discussing with its international lenders to save the country from bankruptcy.

EURO DOWN, COPPER AT 2011 LOW

The euro slipped 0.2 percent to $1.3674.

"It is now expected that markets will not hear a final decision until next week," said Camilla Sutton, senior currency strategist at Scotia Capital in Toronto. "As uncertainty continues, there is substantial downside euro risk."

The U.S. dollar traded 0.1 percent up at 76.45 yen. It had earlier dropped as low as 76.111 yen, close to a record low, ahead of Japan's fiscal half-year end, which tends to see investors unwind their U.S. fixed income assets and repatriate funds.

London Brent oil gained $1.70 to $112.24 a barrel after government data showed crude stockpiles fell much more than expected last week in the United States. U.S. crude rose 52 cents to $87.44 a barrel in choppy trade.

Uncertainty about Europe's debt crisis and the global economy pushed copper prices to new lows for the year.

Three-month copper on the London Metal Exchange fell to $8,274 a tonne, down from Tuesday's close of $8,309. The metal used in power and construction earlier slipped to a new low since November 2010 at $8,234.75 a tonne.

Spot gold was last trading slightly lower at around $1,792 an ounce.

U.S. Treasury debt prices held steady. Benchmark 10-year Treasury notes were up 4/32, yielding 1.923 percent.