After 6 p.m., the formal meeting ended for the day with no resolution, though some participants stayed behind to continue talking. "Senior representatives of major financial institutions reconvened on Saturday with U.S. officials at the New York Fed. Discussions are expected to continue tomorrow," said a spokeswoman for the Federal Reserve.

At about 8 p.m., New York Fed President Timothy Geithner was still at the bank's headquarters. Officials from the New York Fed and various banks were expected to continue working through the night.

Under one plan, either Barclays PLC or Bank of America Corp. would buy Lehman's "good assets", such as its equities business, people familiar with the matter say. Lehman's more toxic, real-estate assets would be ring-fenced into a "bad" bank that would contain about $85 billion in souring assets. Other Wall Street firms would try to inject some capital into the bad bank to keep it afloat for a period of time so that a flood of bad assets don't deluge the market, damaging the value of similar assets held by other banks and insurers. The banks are also looking for the government to somehow financially backstop the bad bank.