The Landmarks Preservation Commission signaled yesterday that it would approve a modified version of the New-York Historical Society’s plan to renovate its historic Upper West Side building, but it stopped short of voting on the project.

In its application to the landmarks commission, the historical society proposes widening its building’s main entrance, elongating some of its windows, adding two wheelchair-accessible ramps, and putting up kiosks outside the neoclassical structure on Central Park West, between 76th and 77th streets.

Critics of the project have said it is part of the historical society’s long-term plan to erect a 23-story residential tower on its property, which they oppose.

The executive director of Landmarks West, Kate Wood, said the commission essentially has given the historical society “a green light to move ahead” with the project. “What we’re really talking about is a 280-foot tower in the front yard of a historic district,” Ms. Wood, who heads the Upper West Side preservation group, told The New York Sun. “The public has the right to full disclosure.”

The president of the landmarks commission, Robert Tierney, urged the historical society to rethink some of the details of the exterior work, but at a public meeting he said overall he was “positively inclined toward the application.” Other commissioners yesterday took turns suggesting project modifications such as eliminating the proposed ramps and kiosks.

The president and chief executive of the historical society, Louise Mirrer, said the renovation and the tower are two separate projects. She added that some opponents of the renovations are unsympathetic to the institution’s goals of raising its profile and attracting more visitors.

Last month, Community Board 7 voted down the proposed renovations, but it is up to the landmarks commission to decide whether the project will go forward. A vote before the commission has not yet been scheduled.