WASHINGTON -- The Federal Reserve is considering contingency plans for expanding its lending power in the event its recent steps to unfreeze credit markets fail.

Among the options: Having the Treasury borrow more money than it needs to fund the government and leave the proceeds on deposit at the Fed; issuing debt under the Fed's name rather than the Treasury's; and asking Congress for immediate authority for the Fed to pay interest on commercial-bank reserves instead of waiting until a previously enacted law permits it in...