The Federal Reserve boosted the amount of dollars central banks around the world can auction to $247 billion, an increase of $180 billion, in an effort to ease a tightening in lending and the worst financial crisis since the Great Depression, the Associated Press reported.

The Fed announced in a statement this morning that it had authorized the expansion of swap lines, or reciprocal currency arrangements, with other central banks in Europe, Canada and Asia.

The Fed also eased a spike in overnight lending rates by injecting $55 billion into two temporary reserves. The Treasury Department said that for the first time ever it would begin selling bonds for the Fed to help the central bank deal with unprecedented borrowing needs.

These efforts are designed to boost consumer confidence and encourage banks to reopen credit lines.

The moves come after four days of economic turmoil have erased about $3.6 trillion in market value, with announcements including Lehman Bros. Holdings Inc. filing for bankruptcy and American International Group Inc. receiving an $85 billion federal bailout.

Yesterday, the Dow Jones industrial average plummeted 450 points after a similar drop on Monday. As of 9 a.m., it was up 126 points to 10,735.70, but fell later this morning.

In a two-minute statement this morning, President George Bush said he shares Americans’ concerns and that he and his advisers are working to stabilize the markets. He did not announce any new policy moves and has not fielded questions about the economic situation this week. He canceled an out-of-town trip to monitor the situation.

Meanwhile, investors fear Washington Mutual Inc. could be the next big financial institution to fall amid reports that the government is helping find a buyer for the savings and loan association, which lost $3.3 billion in the second quarter.