The state of negotiations between the Kenmore-Town of Tonawanda School District and its teachers union went public Tuesday night, when the union president suggested the School Board had rejected a tentative agreement.

“If the board wanted to declare impasse in these negotiations, they should have done so well before we reached a tentative agreement,” Donald Benker, president of the Kenmore Teachers Association, said at the board’s meeting in Kenmore West High School.

Benker was one of three union representatives who spoke at the meeting.

He had hinted at growing tensions last November, when he addressed the board with the silent support of dozens of teachers seated behind him.

“The district goal is to be the premier school district in New York State by 2020,” Benker said at that meeting. “You cannot achieve this vision by giving rhetoric to us. Your vision depends on working with us — not to us.”

The most recent three-year contract between the union, which represents about 800 teachers, and the district expired last summer. Under that pact, teachers received pay raises totaling 4.2 percent, and the district went to a single health insurer.

Tuesday night, School Superintendent Mark P. Mondanaro would not elaborate on Benker’s reference to a tentative agreement or a superintendent’s recommendation that Benker also had mentioned.

“I really can’t comment too much on it because it’s negotiations,” Mondanaro said, citing ground rules about not making public statements.

But a School Board statement, read by Melissa Brinson, board president, said in part:

“Businesses in the private sector are cutting spending and jobs. Families are cutting costs, keeping a close eye on spending and tightening their belts because of the bad economy. This Board of Education must do the same.”

“We are committed to continuing to talk,” the statement concluded.

When asked later about Benker’s comment, Brinson said, “No one has declared an impasse.”