With negotiations stalled over the future of development rights at ground zero, developer Larry Silverstein is moving ahead with site preparation for the Freedom Tower, a project that will cost millions of dollars and take up to six months to complete.

Silverstein Properties is scheduled to begin construction on the Freedom Tower this month. While it is not clear whether the project will proceed as scheduled, the developer has decided to move forward on planned infrastructure improvements.

About two weeks ago, construction crews hired by Mr. Silverstein began to survey the Freedom Tower site and bring in equipment to relocate utility lines that support PATH trains. Crews soon will begin relocating the power lines to make way for foundations for the columns of the 1,776-foot commercial tower, Silverstein officials said.

There was speculation that the uncertainty surrounding the Freedom Tower, which has been at the center of recent negotiations among the developer, the state, and the Port Authority, would cause the developer to hold off on planned construction. The Freedom Tower is believed to be the least commercially attractive site planned for ground zero, and there has been a chorus of critics of its viability, most recently Attorney General Eliot Spitzer, the front-runner to be the next governor of New York.

Last week, construction plans were cast further in doubt when a proposal floated by Governor Pataki to end an impasse between the developer and the Port Authority, which owns the site, was turned down. That proposal would have transferred the responsibility for the Freedom Tower and another commercial tower near ground zero to the Port Authority from Mr. Silverstein.

Members of the board of commissioners of the Port Authority, led by New Jersey appointees, expressed reservations about Mr. Pataki’s plan, saying it would negatively impact the balance sheet of the Port Authority, a bi-state agency. They also sought more money to pay for the planned memorial on the site.

Yesterday, the city and state comptrollers, William Thompson and Alan Hevesi, joined the list of New York politicians who are asking Governor Corzine to avoid further delay in negotiations regarding ground zero. Last week, the New York congressional delegation wrote a letter asking Mr. Corzine to overlook the “revenue goals” of New Jersey in favor of ending negotiations promptly.

Mayor Bloomberg has defended Mr. Corzine, saying that the governor is not responsible for delays at ground zero, and that he has a right to protect the interests of New Jersey.