The truce called yesterday in the battle between Mayor Bloomberg and the teachers union president over plans to reorganize the school bureaucracy is likely to be shortlived, with fighting expected to erupt again soon over class size reduction and teacher tenure.

The mayor agreed yesterday to water down one of the cornerstones of his new schools initiative — a school funding formula that would base school budgets on students, not teacher salaries — after days of marathon negotiations with the some of the biggest critics of his education plans, the president of the United Federation of Teachers, Randi Weingarten, and the Working Families Party.

Speaking to reporters with Ms. Weingarten, Working Families officials, immigrant advocacy groups, the City Council speaker, Christine Quinn, and the City Council education chairman, Robert Jackson, behind him, Mr. Bloomberg also announced that “in spite of all the yelling and screaming” during the past several months, he is planning to consult more closely with the groups on education policy decisions in the future.

“We don’t agree on everything,” he said. “Over the past few days, we’ve realized that we are a lot closer together on many of the issues surrounding school initiatives than some might have thought.”

The main piece of the agreement is a change to the mayor’s proposal to make school budgets more equitable. The current system allows schools to continue receiving the same amount of money for a highly paid teacher’s salary even after that teacher retires, which the mayor has said is the cause of vast funding disparities between schools. His original plan was to take away the extra money once highly paid teachers retire.

The teachers union argued that the mayor’s proposal would create a disincentive for schools to replace the expensive teachers with similarly paid teachers, and persuaded the mayor to allow schools to keep the extra funding following their retirement.

While the focus of the announcement yesterday was on the newfound peace brokered between the two sides, it is unlikely to last.

Although the union agreed to the compromise, it is continuing to pursue a grievance that would extend the hold on teacher salary funding to teachers who transfer, not just teachers who retire — a move that further undermines the mayor’s proposal.

When asked about the grievance, the schools chancellor, Joel Klein, said it had no merit.

Mr. Klein also said that while he and the mayor will consult with a new task force created under the agreement on issues such as reducing class size and strengthening teacher tenure requirements, the administration will still have the final say.

“What we agreed to was to have consultations,” he said. “The agreement starts and couldn’t be clearer with the recognition by everybody that the decisions on these things are to be made by the mayor and the chancellor.”

A parent leader, Tim Johnson, the president of the Chancellor’s Parent Advisory Council, noted that one group was left out of the bargaining room: parents. The exclusion of parents has been the rallying cry of many of the mayor’s critics, but Mr. Johnson said no elected parent leaders were invited to work on the agreement.

“Not one elected parent leader stood with the mayor today,” he said. “This agreement provides no relief for disenfranchised parents, who were once again denied a seat at the table.”