DETROIT  The Treasury Department is directing Chrysler to prepare a Chapter 11 bankruptcy filing as soon as next week, people with direct knowledge of the talks said Thursday.

The company faces a deadline of April 30 to come up with a viable business plan supported by its creditors, the United Automobile Workers union, and Fiat, the Italian car company that wants to acquire a stake in Chrysler.

The Obama administration has told Chrysler it will provide up to $6 billion in new financing, on top of the $4 billion in loans it has already given the company, if Chrysler can complete a deal by next Thursday with a cost structure that gives it a chance of survival. The creditors have so far balked at the terms suggested by the Treasury.

But the negotiations have taken a new direction. Treasury now has an agreement in principle with the U.A.W., whose members’ pensions and retiree health care benefits would be protected in the event of a bankruptcy filing, said the people with knowledge of the discussions, who asked for anonymity because they were not authorized to discuss the case.