NEW YORK (AP) — The city defended its groundbreaking size limit on sugary drinks Wednesday as an imperfect but meaningful rein on obesity, while critics said it would hurt small and minority-owned businesses while doing little to help health.

The first courtroom arguments in the closely watched case ended without an immediate ruling — and with opponents saying they planned to ask a judge to delay enforcement during the suit, which has broached questions of racial fairness alongside arguments about government authority and burdens to business.

The NAACP’s New York state branch and a network of Hispanic groups have joined a legal effort to block the first-of-its-kind restriction, igniting questions Wednesday about the groups’ ties to the beverage industry.

Beverage makers, restaurateurs, minority advocates and other critics told a judge the upcoming 16-ounce limit was a finger-wagging incursion on consumer choice, rife with inconsistencies that would cost a hot dog vendor business while still allowing New Yorkers to buy belly-buster sodas at the chain convenience store next to him. Opponents’ lawyers called it ‘‘ham-handed,’’ ‘'grossly unfair’’ and just ‘‘plain silly.’’

‘‘New Yorkers do not want to be told what to drink,’’ attorney James Brandt said.

City lawyers acknowledged the rule’s limitations. It doesn’t apply to all high-calorie drinks or all places that sell them, largely because of the city can regulate only some establishments. But it’s still a reasonable and needed move to take on the city’s growing weight problem and the diseases linked to it, they said.

‘‘While this may not be a silver bullet that will cure the obesity epidemic, it’s rational ... (and) one step that can be taken,’’ said the city Health Department’s chief lawyer, Thomas Merrill.

The suit, filed by the American Beverage Association and others, seeks to block the restriction, set to take effect March 12. With no immediate ruling Wednesday, opponents said they planned to ask state Supreme Court Justice Milton Tingling to put it on hold until the case is decided. The city will oppose such a move, Merrill said after the hearing.

The latest in a line of healthy-eating initiatives during Mayor Michael Bloomberg’s administration, the beverage rule bars restaurants and many other eateries from selling high-sugar drinks in cups or containers bigger than 16 ounces. Violations could bring $200 fines; the city doesn’t plan to start seeking those until June.

In explaining the cola crackdown, officials cite the city’s rising obesity rate — about 24 percent of adults, up from 18 percent in 2002 — and point to studies linking sugary drinks to weight gain. Care for obesity-related illnesses costs more than $4.7 billion a year citywide, and government programs pay about 60 percent of that, according to city Health Commissioner Dr. Thomas Farley.

Opponents portray the regulation as government nagging that scapegoats sugary drinks for a multifaceted fat problem, and they say the restriction is unfairly narrow.

Unsweetened juice and milk-based drinks are excluded; health officials say they have nutritional value. The regulation also doesn’t cover alcoholic drinks or sales at supermarkets and many convenience stores — among them 7-Eleven, home of the Big Gulp — because they aren’t subject to city health rules.

The NAACP and the Hispanic Federation, a network of 100 northeastern groups, say their concern is that minority-owned delis and corner stores will end up at a disadvantage compared with grocery chains.

But others are underscoring the groups’ links to the soda companies whose fight they've joined. Among the ties:

— Coca-Cola announced last month it was giving a $100,000 grant to the national NAACP to support a healthy-lifestyles program

— PepsiCo gave the group more than $10,000 in 2010, according to the soda maker’s website.

— Former Hispanic Federation President Lillian Rodriguez Lopez left for a job at Coca-Cola in in February.

— The groups were represented Wednesday by a firm that also has represented Coca-Cola. The firm, King & Spalding, is representing the advocacy groups for free, lawyer Ann M. Cook said.

Given that obesity rates are higher than average among blacks and Hispanics, the NAACP should refuse soda makers’ money and ‘‘reevaluate the position the group is taking in New York City,’’ Michael F. Jacobson, the executive director of the nutrition advocacy group Center for Science in the Public Interest, said in a statement Wednesday.