In a rare display of internal disagreement at City Hall, Mayor Bloomberg yesterday nixed his advisers’ efforts to open the food stamp program to more adults who don’t have children.

The mayor’s top social services aides wanted to seek a federal waiver to loosen eligibility requirements. The plan to pursue the waiver was described in detail on the front page of yesterday’s New York Times as a done deal. But City Hall officials said yesterday that the mayor had not made a final decision.

In an e-mail to reporters yesterday afternoon, Deputy Mayor Linda Gibbs, who oversees social service programs, said the city had taken “preliminary steps to relax eligibility rules,” but would not pursue the waiver after all.

“After further consideration, we have decided that this potential policy change is not consistent with the mayor’s goal of helping New Yorkers become self-sufficient,” she said.

City Hall sources described both Ms. Gibbs and the commissioner for Human Resources Administration, Verna Eggleston, as supporters of the waiver efforts.

Welfare advocates who began the day excited about the report ended the day expressing shock at City Hall’s decision to abandon the waiver request.

The waiver would have eased the eligibility requirements for thousands of adults between the ages of 18 and 49 who do not have dependent children and are fit for work. Adults with and without jobs would fall under that umbrella.

Mayor Giuliani decided a decade ago to forgo the waiver, which would have extended a three-month federal limit on food stamps for this group of adults. Other large cities have already tapped the waiver because the food stamps are paid for by the federal government.

“They decided not to do a substantive thing for the wrong political reasons,” Rep. Anthony Weiner, a Democrat who represents Queens, said. “I think it’s just the politics of being tough. I think they chose the appearance of being tough over the reality of doing the right thing and that’s regrettable.”

Early yesterday, Mr. Weiner, who ran for mayor last year, issued a statement commending the mayor for pursuing the waiver, but later in the day he was criticizing the decision.

“I don’t know where the wheels fell off the decision train here,” he said. “It could just be that he woke up read it in the paper and said this isn’t something I believe in.”

Council Member Bill de Blasio, who is the chairman of the council’s General Welfare Committee, said it “makes no sense.”

“I am very dismayed,” he said. “His own social service commissioner told us weeks ago that the city was going to have a very difficult time complying with the new federal regulations for welfare reform.”

“Cities and counties all around New York State take this waiver, including Republican-led counties,” Mr. de Blasio said.

In her statement, Ms. Gibbs, one of the mayor’s most trusted advisers, said the city will continue to monitor the situation and may consider seeking a waiver next year. She also said the Bloomberg administration has been working to make it easier for those New Yorkers who are eligible.

Mr. Bloomberg has an April 26 deadline to file for the waiver.

The president of the Food Research and Action Center, James Weill, said it is unfortunate that the mayor did seek the waiver earlier.

“I don’t know what the motives are,” Mr. Weill said. “Not seeking the waiver or putting it off until next year is a very bad mistake. The waiver would let the food stamp program in the city reach more unemployed, desperately needy people.”