Teachers in the Alexandria public school system are expected to ask for an 18 percent pay raise tonight when the last scheduled round of contract discussions with school officials is held.

Teachers' representatives, however, face a tough battle in winning approval for the increase. The request is 10 percent higher than budget guidelines set by the city manager and exceeds anticipated increases in the overall school budget.

Although no firm figures have been established, school officials said unless further cuts are made, next year's school budget could be 12.5 to 15 percent higher than this year's $40 million budget.

"It would be very unrealistic to think that we could stick to the 8 percent limit (on budget increases set by the city) unless drastic cuts in services were made," said William Leonard, assistant superintendent for finance and data.

Leonard would not say what provisions were being made for teachers' salary increases, but he indicated that a "very conservative estimate" based on the city's guidelines was being considered. Teachers' representatives, concerned that this might mean an increase of only 8 percent, said the figure was unreasonable.

"We're rather aghast at the idea . . . the last few years we've lost a lot due to inflation. And that type of increase (8 percent) doesn't catch up by any stretch of the imagination," said John Raiford, president of the Education Association of Alexandria, which represents 665 of the city's 797 teachers.

In addition to the salary increases, Leonard said the budget will include major increases for energy costs, transportation, special education and unemployment compensation.

If a final agreement with teachers can be reached tonight, the proposed budget will be presented to the school board at a work session Jan. 28. A public hearing is scheduled Feb. 11 before the final board vote Feb. 23. The budget then would be sent to the City Council for approval.

Tonight's meeting, which is open to the public, begins at 8 p.m. at the Minnie Howard School Administration Building, 3801 W. Braddock Rd.