The Dow Jones Industrial Average and S&P 500 has vaulted to new records after Federal Reserve Chairman Ben Bernanke pledged to maintain the Fed's easy-money policy for the foreseeable future.
The Dow surged 169.26 (1.11%) to 15,460.92, well above the previous high of 15,409.39 on May 28. The S&P 500 gained 22.40 (1.36%) to 1,675.02, up from it prior record of 1,669.16 on May 21.
The Nasdaq Composite meanwhile added 57.54 (1.63%) to 3,578.30.
Dr Bernanke, speaking in Boston late on Wednesday afternoon, promised to keep interest rates low due to the weak economy, suggesting a slower time-frame to tapering the Fed's aggressive bond-buying program.
The comments surprised markets, which have been bracing for the Fed to scale back the bond-buying program as soon as September.
"I don't think there's any immediate Fed tapering in the future," William Lynch, director of investments at Hinsdale Associates, said.
Mr Lynch said markets are also hopeful that the upcoming earnings season will surprise to the upside, given that expectations are low.