(Updates with market action after Fed rate cut)
By Richard Satran
NEW YORK, Jan 30 (Reuters) - Wall Street stocks climbed sharply on Wednesday after the U.S. Federal Reserve made an aggressive half-percentage-point cut in key interest rates in a move to bolster a U.S. economy that staggered toward recession at year end.
The dollar fell sharply, and key commodities recovered from early declines. U.S. Treasury bonds cut earlier losses.
Before the Fed decision, traders were evenly split over whether the central bank would cut benchmark U.S. rates by half a percentage point or a quarter point in its two-day policy meeting.
In trading just after the cut, the Dow Jones industrial average <
> was up 78.04 points, or 0.63 percent, at 12,558.34. The Standard & Poor's 500 Index <.SPX> was up 9.02 points, or 0.66 percent, at 1,371.32. The Nasdaq Composite Index < > was up 15.08 points, or 0.64 percent, at 2,373.14.The Fed set up expectations of an aggressive move after it made a 3/4-point rate cut in an emergency action last week. Skepticism grew over another sharp cut on scattered signs of U.S. economic recovery and concern that the Fed's emergency measure may have been a flawed response to short-term market declines sparked by a rogue trader at French bank Societe Generale <SOGN,PA.>.
Rate cut hopes rose again early on Wednesday, though, on a report that U.S. economic growth last year dropped to a five-year low of 2.2 percent, with a fourth-quarter gain of just 0.6 percent, half the expected rate.
Earlier, European stocks and the dollar were hit as UBS <UBSN.VX> unveiled $4 billion in new write-downs, stirring fears of a deepening credit crisis. UBS was among the hardest-hit of the banks around the world that have collectively suffered more than $100 billion in losses from the crisis originating from defaults in U.S. subprime mortgages.
The big Swiss bank's charges reminded investors that the Fed action can do nothing to help results in the earnings season starting on Wall Street.
"The fourth-quarter reporting season will be a real acid test for the banks," said Franz Wenzel, strategist at AXA Investment Managers in Paris. "Most of the banks will try to put all the write-downs in their 2007 results as they want to clean the balance sheet going forward."
Some investors were betting that the bottom has already been reached in a recession that probably began last year. The view gained support early in the day as private data provider ADP reported 130,000 new U.S. private-sector jobs were created in January, three times forecast. In the prior session, a surge in durable goods orders for December surprised markets.
Investors were less concerned over the impact of higher prices, which the Fed must worry over as it stimulates the economy. Commodities drifted lower on the surprising decline in fourth-quarter GDP growth.
"The Fed understands that it needs to make hay while the sun shines by pumping as much liquidity into the economy now, while it still can, before the public's inflation expectations catch up with reality," said John Kosar, president of Asbury Research in Chicago.
Gold on the New York futures market <GCJ8> jumped $4.20 to $935 after the rate cut, after falling as low as $926.
In the U.S. Treasury market, the benchmark 10-year note <US10YT=RR> was trading 14/32 lower in price for a yield of 3.73 percent from 3.68 percent late on Tuesday, while the two-year note <US2YT=RR>_was flat in price for a yield of 2.30 percent. (Reporting by Gertrude Chavez-Dreyfuss, Ellis Mnyandu and Pedro Nicolaci da Costa; Writing by Richard Satran; Editing by Jonathan Oatis)