NEW YORK — Mayor Zohran Mamdani is backing a City Council proposal that would require Amazon and other large delivery operators to directly employ workers who handle last-mile deliveries, putting the mayor at odds with Amazon and businesses that rely on its delivery network.

The Delivery Protection Act would limit the use of subcontractors for key warehouse and delivery operations and require covered companies to put those workers on their own payrolls.

Mamdani said Monday that the proposal would give delivery workers greater protections and make major corporations more accountable for the conditions surrounding their operations.

Amazon has warned that the legislation could fundamentally change its New York delivery network and lead the company to move some operations outside the city.

The company says that could jeopardize thousands of jobs at local delivery businesses and make deliveries to New Yorkers slower and more expensive.

Amazon currently works with dozens of independent Delivery Service Partners in the city, collectively employing more than 5,000 people. The company says those businesses could be undermined if the direct-hiring requirement takes effect.

An economic analysis cited by opponents estimated that the legislation could cost the average New York household hundreds of additional dollars annually for deliveries. The estimate is disputed and would depend on how companies respond to the new requirements.

Business groups and delivery operators have also raised concerns about the impact on small companies that contract with Amazon.

Rudy Cazares, who operates an Amazon delivery company and also works as a FedEx contractor, said the proposed rules could force him to close his business. He said his company employs about 130 workers and provides full- and part-time jobs with benefits.

Supporters of the legislation, including the Teamsters, argue that delivery companies should be directly responsible for workers performing essential parts of their business rather than relying on layers of subcontractors.

The New York Delivers coalition, which opposes the bill, planned a demonstration in East Harlem featuring delivery workers and small-business owners who say the measure threatens their jobs and businesses.

The coalition estimates that up to 10,000 delivery positions could be affected.

The debate has placed Mamdani alongside organized labor in a growing fight over how packages are delivered throughout New York City.

City officials have said lawmakers should examine possible unintended consequences before adopting the measure, while the City Council continues to consider the legislation.