The Bush administration sketched out a multi-faceted effort on Friday to confront the worst U.S. financial crisis in decades, outlining a program that could cost taxpayers hundreds of billions of dollars to buy up bad mortgages and other toxic debt that has unhinged Wall Street.

The government steps were clearly welcomed by financial markets. As Paulson spoke, the Dow Jones industrials were up over 300 points and at one point had soared by 450 points

President Bush, flanked by Treasury Secretary Henry Paulson and Federal Reserve Chairman Ben Bernanke, acknowledged that the program will put a "significant amount of taxpayers' money on the line."

The administration is asking Congress to give it sweeping new powers to execute the plan. Paulson said it "needs to be big enough to make a real difference and get to the heart of the problem."

Paulson gave few details but said he would work through the weekend with leaders of Congress from both parties to flesh out the program, the biggest proposed government intervention in financial markets since the Great Depression. Members of the Senate Banking Committee said they had received no details of the proposal.