"He is planning to move ahead with Seven World Trade Center," the spokesman says. "He hopes to be in the ground with the Con-Ed substation by June of this year and six months after that he hopes to start construction on the tower above it. The substation is the first phase."

While plans for the tower have not been released, the new building will be "comparable in the amount of office space to what Seven World Trade was before," the spokesman said. Silverstein has hired Tishman Construction Corp. as well as architecture firms Skidmore, Owings & Merril and Cooper Roberts Simonsen for the project.

Seven World Trade Center was a 47-story, two-million-sf office tower with a tenant roster that included American Express Co., the New York City Mayor's Office of Emergency Management, Salomon Smith Barney and the US Securities and Exchange Commission.