Global stocks and the Euro rallied on Wednesday after the world's leading central banks agreed to cut the cost for European banks to borrow much-needed dollars.
US stocks rose 3% as major central banks jointly added liquidity to the world's financial system, easing worries about a global downturn.
The Dow Jones industrial average was up 408.11 points, or 3.53%, at 11,963.64. The Standard & Poor's 500 Index was up 41.92 points, or 3.51%, at 1,237.11. The Nasdaq Composite Index was up 83.45 points, or 3.32%, at 2,598.96.
European shares rallied in tandem with other risk assets after leading central banks announced joint action to inject liquidity into financial markets strained by the Euro zone's debt crisis.
As a result, the FTSEurostocks 300 rose 3.6% in its fourth consecutive day of gains, climbing back to levels not seen since mid-November.
Asian stocks also fell sharply overnight, with China's benchmark posting its biggest one day fall since August 8 on concerns about growth in the world's second-largest economy.
The Nikkei share average ended lower, reversing two days of gains on profit-taking as investors remained cautious over new developments in the Euro zone debt crisis and looked to data later in the week.
The benchmark Nikkei ended the day down 0.5% at 8,434.61, and lost 6.2% in November. The broader Topix index shed 0.2% on the day to 728.46.