WARWICK — The city’s teachers have agreed to defer part of the 3.5 percent salary increases they were slated to receive this year in return for a two-year contract extension that keeps their contribution to their health insurance premiums at a flat $11 per week.

The School Committee, in a 3-2 vote, last night ratified the amended agreement that extends the life of the contract with the Warwick Teachers Union to 2011. Majority members said the salary deferral allows the district to pare about $1.4 million from the roughly $4-million deficit projected for this year.

The current-year schools budget will still have to cover more than $4.6 million in back pay to teachers from the last contract settlement, in 2006, which not only extended forward for three years but had to cover the prior three years when teachers worked without a contract and without raises.

Committee members Joyce Andrade and Paul Cannistra voted against the contract extension, saying the district could not afford to make no changes in teacher contributions to health care premiums for the next three years.

“We have urgent fiscal concerns,” Andrade said. “I don’t agree that a two-year [extension] with no significant changes in language or health care [premiums] is the best way.”

Andrade also expressed disappointment that the teachers union had not been willing to consider her proposal that they consider deferring their retroactive pay.

Committee Chairman Christopher E. Friel said the district wants to move toward greater employee contribution to health care costs. But in the face of the current fiscal crisis, he said, the board needed to find major savings and that could happen only through concessions to its biggest labor union.

“This gives us a much-needed cost saving from our largest sector of employees,” Friel said. “I view this teachers contract renegotiation and extension as the first step in bringing the district back on stable fiscal footing this year and for the next two years.”

Under the terms of the contract extension, the teachers will receive a 2 percent, rather than 3.5 percent, pay raise this year. The balance of the original raise will be paid in lump sums when teachers retire or resign from the district.

Depending on which of the 10 salary steps a teacher is on, those lump-sum payments will range from about $560 to $1,045, according to information provided by the School Committee last night.

The contract extension also gives teachers a 2.25 percent pay raise next year and a 2.75 percent raise the following year, 2010-11.

Cannistra called the agreement “egregious” and said that the school board was “walking away from the opportunity to make changes in health care.” He also warned that the School Committee “in its irresponsibility” might get blamed if the city can’t negotiate more health care premium concessions with its unions in the next couple of years.

Vice Chairwoman Lucille Mota-Costa said she, too, would have liked more concessions in the health coverage language but that the contract extension is enabling the school board to take care of its main responsibility to “stabilize this school district.”

Although the district still faces a sizable deficit and some hard choices, Friel said, the import of the $1.4-million savings this year is crucial.

He also alluded to past acrimonious relations between the school board and the teachers union. The district, he said, now not only has a clear picture of its future expenses but is ensured “the smooth operation of the Warwick School Department for an additional two years.”

“While this does not translate into dollars and cents, to any parent of a Warwick school student it is equally important,” Friel said.

bpoliche@projo.com