Less desirable assets, brands like Hummer and underperforming factories, would be left in the old company. Proceeds from the sales, including stock in the new company, would be given to the old G.M., helping to settle claims.

The plans are still being discussed, and the details are subject to change, people familiar with the talks said.

G.M. joins a long list of companies in industries like airlines, railroads and steelmakers that have faced the prospect of being remade in bankruptcy. Typically, a troubled company usually seeks to line up creditors, employees and other stakeholders for a plan of reorganization before a bankruptcy filing. Failure to achieve this agreement can create a prolonged and messy court process as the company battles its creditors while its business and financing rapidly deteriorate.

Elements of the government’s plans for G.M. are in some ways similar to the demise of Lehman Brothers last fall. A day after filing for Chapter 11 protection, the securities firm agreed to sell the bulk of its North American business to Barclays Capital, the British bank. The sale was completed in a little more than three days.

The administration hopes to win support from some of G.M.’s creditors, notably the United Automobile Workers, which would be forced to pare its health care benefits and whose pension obligations would probably remain in the old company. But the bankruptcy code allows a judge to approve a sale even over creditor objections in an emergency under Section 363, legal experts say. Such was the case with the Lehman sale.

While the automaker would not be the biggest company ever to file for bankruptcy protection  Lehman holds that dubious distinction  it is woven into a complex international web of suppliers and subsidiaries. One goal of any reorganization plan would be to minimize disruption to other businesses.

“This would rank as one of the most, if not the most complex bankruptcy in history,” said Stephen F. Cooper, founder and former chairman of Zolfo Cooper, a turnaround firm. Mr. Cooper, who ran Enron during its bankruptcy, added that politics would influence any plan.