His administration has tried other ways to discourage soda consumption. The mayor supported a state tax on sodas, but the measure died in the Legislature, and he tried to restrict the use of food stamps to buy soda, an idea federal regulators rejected.
Legal experts said the soft drink industry may mount a challenge to the new rule by arguing that it's arbitrary or internally inconsistent.
Given that you can't buy a 32-ounce serving but you can buy two 16-ounce ones, "a court might say that all it does is help the cup industry by making people buy more cups," said John Humbach, a professor at Pace Law School. But he called that approach "a long shot."
(Bloomberg isn't against all sugary treats. He recently issued a proclamation declaring Friday as NYC Donut Day, honoring an annual tradition launched 75 years ago to honor women who served the treats to soldiers. City Hall officials emphasized the proclamation doesn't represent Health Department policy.)
Mark Kalinowski, an analyst with Janney Capital Markets who covers companies such as McDonald's, predicted an uproar.
"Folks who want to buy Big Gulps and Frappuccinos, a lot of those customers, you're only going to be able to take it away from them by prying it out of their cold, dead hands," he said.
If the ban goes into effect, he said, customers will probably just respond by ordering two drinks.
"Maybe the mayor can outlaw all soft drinks and outlaw all fun while he's at it," Kalinowski scoffed.
Follow Samantha Gross at www.twitter.com/samanthagross
AP Food Industry Writer Candice Choi and writers Karen Matthews and Verena Dobnik contributed to this report.
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