WASHINGTON — The government outlined a financial rescue plan for student loan companies on Wednesday, offering to buy federally subsidized loans that lenders such as industry giant Sallie Mae said had become unprofitable.

The action is intended to protect lenders from losses over the next year and make sure that students have uninterrupted access to loans, the Secretary of Education, Margaret Spellings, said in a letter Wednesday that detailed the plan.

Under the plan, lenders will have the option of selling the government securities backed by student loans on terms markedly more favorable than the rates now available in the financial markets.

The chief executive of Sallie Mae, Albert Lord, whose company had said it might stop making federal loans, hailed the announcement as “practical, workable, and maybe most of all quite helpful.”

Sallie Mae, based in Reston, Va., had heightened the drama by scheduling an afternoon conference call with college officials. On the call, Mr. Lord said he did not know until he read Ms. Spellings’s letter at 1:08 p.m. what direction the call would take, implying that the company had been on the verge of withdrawing from the federal loan business.

Government officials drove a hard bargain, Mr. Lord said, but under the administration’s plan, Sallie Mae’s commitment to the program “is virtually unbounded.” An executive at the American Association of Collegiate Registrars and Admissions Officers, Barmak Nassirian, called the plan a bailout.

“Certainly the scale of this intervention may well exceed any emergency, any theoretical emergency we may face,” Mr. Nassirian said. “Sallie Mae … threatening to exit federal student lending is as credible as Starbucks threatening to leave the coffee business.”

In taking this initiative, the government was responding to a threat that has the potential to become a political issue in an election year. Last year, Congress and President Bush enacted legislation cutting subsidies on government-backed loans. Some politicians argued that federal programs had showered excess profits on private lenders. Meanwhile, the credit crunch that began in the mortgage market spread to other sectors, making it costlier for lenders to sell student loans to investors and thereby replenish the funds needed to make more loans.

Dozens of lenders exited the federally backed student loan business, including many of the largest, and the industry pleaded for relief. Congress recently passed legislation paving the way for the administration to intervene.

“These offers of temporary federal support ensure lenders have the incentives, and, if necessary, the liquidity needed to continue serving students and families for the 2008-2009 academic year,”

Ms. Spellings said in the letter. Lenders will have the option of selling the Education Department loans for the coming academic year. The payment would include $75 a loan to reimburse lenders for administrative costs.