The city is considering banning cars from Central Park 24 hours a day, seven days a week during the summer, the recently appointed transportation commissioner, Janette Sadik-Khan, told a group of about 2,000 cyclists on Sunday.

The statement by Ms. Sadik-Khan, herself an avid cyclist, marks a departure from her predecessor, Iris Weinshall, who had vetoed a similar plan arguing that closing the park’s roadway loop to motorists would worsen congestion and pollution throughout Manhattan.

Cars were first allowed to drive on the roadway in 1899, and by permit only, according a spokesman for the advocacy group Transportation Alternatives, the group that has been leading the campaign for a car-free Central Park. A poll by Transportation Alternatives found that among respondents one in 10 visitors to the park were injured by a vehicle, and 64% would use the park more if vehicles were banned.

A spokesman for the transportation department said the city was considering the plan after receiving several requests from City Council and transit advocates. It was too early to say when the program might begin, he said. The president of Manhattan, Scott Stringer, five Council members, and the public advocate, Betsy Gotbaum, have all endorsed the initiative.