The public will have its only crack at opposing developer Larry Silverstein’s application for $3.35 billion in tax-exempt financing to construct 10 million square feet of office space at ground zero at a hearing scheduled for tomorrow.

The board of the Industrial Development Agency is scheduled to vote next Tuesday on the remaining Liberty Bonds, which will save the developer millions every year.

Mr. Silverstein, who controls the site through a 99-year lease with the Port Authority, has indicated that the tax-exempt financing is necessary to complete his proposed $8 billion project, which includes the Freedom Tower and at least three commercial office towers.

Mr. Silverstein said yesterday that he is now discussing construction timetables and performance guarantees with city officials.

“I can give the city and state an absolute guarantee that all of the Liberty Bonds will be used and that I will build these buildings on the most aggressive schedule,” Mr. Silverstein told The New York Sun.

Mayor Bloomberg has tirelessly advocated for more residential development at the World Trade Center site and expressed frustration with the slow progress of development.

Earlier this fall, city officials suggested that some of the remaining Liberty Bonds be allocated to other projects, but currently there are no serious contenders for the remaining tax-exempt financing, which is only applicable to commercial developments.

The president of the Real Estate Board of New York, Steven Spinola, who supports the application, said yesterday that if the bond allocation is approved next week, the details of the development plan could be changed at a later date by the board.

“Right now, in December 2005, this is the authorization that is needed. If market conditions or other things change over time, practical people are going to do what is best for everybody in the end. This is the kind of step that is necessary at this point in time,” he said yesterday.

Not everyone is convinced, however, that the bond allocation is the best use of public subsidies.

The director of a development accountability think tank, Good Jobs New York, Bettina Damiani, will testify against Mr. Silverstein’s application tomorrow. She said that proposed, city subsidized commercial development on the far West Side and at the Atlantic Yards site in Brooklyn could flood the city with vacant office space.

“Do we need to subsidize so much office space that right now the downtown market seems not to need?” Ms. Damiani said yesterday. “This is a significant subsidy with large ramifications. We need to make sure our resources are used wisely.”

Yesterday, Mr. Silverstein was optimistic about the demand for downtown commercial space.

“All of the recent reports demonstrate increased demand and absorption. For companies that want large blocks of modern, efficient, and centrally located office space but can’t afford Midtown asking rents, there really will be no alternative but downtown in the coming years,” he said.

Some have suggested that a staggered allocation of Liberty Bonds or tying them to a construction timetable would add leverage to the city’s negotiations with the private developer.

The chief of staff for Rep. Jerrold Nadler, a Democrat of Manhattan, Amy Rutkin, said yesterday, “It would be a good thing if there were a means to ensure that promises are kept, provided that it does not slow the process.”

The IDA board, which is made up of representatives appointed by the mayor, the five borough presidents, the comptroller, and the law department, has the authority to accept, reject, or modify the application. After approval, changes in the application must be cleared with the board.

Ms. Damiani, of Good Jobs New York, also expressed concern that the application could change at a later date without the opportunity for the public input.