The horse-drawn carriages that clip-clop around Central Park in New York City could be banned under City Council legislation to be introduced at the urging of animal advocates who say the horses are treated inhumanely.

Councilman Tony Avella, who planned to introduce the bill on Wednesday, said the horses were exposed to cruel conditions and were in danger in city traffic. In September, a horse died after it was spooked by street musicians and bolted down Central Park South.

“The animals are not being treated properly, and enough is enough,” said Mr. Avella, a Democrat from Queens. “Horses are incompatible with traffic, especially Midtown traffic.”

Mayor Michael R. Bloomberg said last week that the horses should remain. “These are things that the tourists like and New Yorkers like, and they define a city,” he said