On the second Friday in October, Mayor Bill de Blasio met at City Hall with Steven Roth, one of New York City’s most powerful real estate developers.

On the agenda: the developer’s concerns about Mr. de Blasio’s plans to transform Fifth Avenue, New York City’s most famous shopping corridor, into a thoroughfare that prioritized buses over cars.

Within days of the meeting, Mr. de Blasio’s transportation commissioner asked staff to reconsider the plan the mayor had announced more than a year before, according to two people familiar with the decision who were not authorized to speak publicly.

Around the same time, a slide show presentation dated Oct. 7 bearing the name of Mr. Roth’s real estate company, Vornado Realty Trust, began circulating in City Hall.

“Express buses traveling at faster rates create anxiety for pedestrians and bikers and make the avenue more dangerous,” the presentation warned. “Fifth Avenue tourists are especially at risk.”

The Fifth Avenue project was supposed to have been completed before Mr. de Blasio left office, but the city announced last week that work would be put on hold until after the December holidays. That effectively shifts responsibility to the next mayor, who succeeds Mr. de Blasio in January.

The city’s transportation commissioner, Hank Gutman, told reporters that the city did not want to risk “interfering with the holiday season.’’

Vornado Realty Trust, the self-described “largest owner and manager of street retail in Manhattan,” controls 2.7 million square feet of Manhattan retail space, including storefronts along Fifth Avenue occupied by Harry Winston, Salvatore Ferragamo and the North Face.

Credit… Taylor Hill/FilmMagic, via Getty Images

Mr. de Blasio’s decision to reconsider the busway on Fifth Avenue came not long after the transportation department said it planned to move forward with the street redesign.

The mayor’s change of heart comes as he is actively piecing together a bid for governor of New York State. The developer, the Vornado Realty Trust chief executive Steven Roth, is one of New York’s most prolific donors, though city records indicate he has not donated to Mr. de Blasio’s mayoral campaigns.

A spokesman for Mr. Roth declined to comment. A spokeswoman for the mayor, Danielle Filson, said, “This administration installed a record number of bike lanes, bus lanes, and busways last year — in a budget crisis and a pandemic-shortened installation season. We’re going to beat those records this year, and this busway will be part of that legacy.”

Mr. de Blasio’s ambivalence about the Fifth Avenue plan comes during the deadliest year for traffic fatalities during his eight years in office and as some of his other transportation priorities appear to have fallen by the wayside. The transportation department has been reconsidering plans to put a protected bike lane on a main thoroughfare in Sunset Park, Brooklyn according to one of the two people familiar with the mayor’s decisions.

Though Mr. de Blasio does not oversee the buses, which are operated by the state-controlled Metropolitan Transportation Authority, he does control the city’s streets.

In June 2020, he announced he would turn over 20 miles of streets to buses, installing 3.5 miles of busways along five major thoroughfares and an additional 16.5 miles of dedicated bus lanes. Busways severely restrict local car traffic as a way to increase bus speeds and reliability.

More than 40 different bus routes serving all five boroughs run down Fifth Avenue, and congestion there can delay service citywide. Before the pandemic, 75,000 bus riders made daily trips on the avenue.

A spokesman for the M.T.A. offered a thinly veiled criticism of the city’s decision on the Fifth Avenue busway.

“We hope that yielding to business groups in this situation does not signal a weakening of the city’s commitment to bus priority and moving bus riders faster,” said Tim Minton, the authority’s communications director.

Mr. Gutman is expected to deliver testimony on Tuesday about street safety before the New York City Council.

Mr. de Blasio has faced growing pressure from transit advocates to put in more busways after the success of the 14th Street busway in Manhattan, which all but banned cars in 2019 from a major crosstown route that had once been jammed with 21,000 vehicles a day. Since then, the busway has increased bus speeds and ridership.

Besides Fifth Avenue, Mr. de Blasio announced four other busways: one in northern Manhattan, two in Queens and one in Brooklyn. Three have been completed and a fourth, in Queens, is opening this week.

The Fifth Avenue busway, proposed for a 1.1-mile stretch, would have been the longest of the five.

Its fate is likely to be up to Eric Adams, the Democratic nominee and Brooklyn borough president, who is the heavy favorite to win the election. Mr. Adams has said he would add 150 miles of new bus lanes and busways in four years.

But a spokesman for Mr. Adams declined to comment on his intentions for the Fifth Avenue busway.

The plan Mr. de Blasio is delaying is a more car-friendly version of his original proposal.

The city had wanted to bar most vehicles, except for buses, bicycles and emergency vehicles, from driving continuously along Fifth Avenue, between 34th and 57th Streets.

If other drivers wanted to access the avenue, they would have had to do so from a side street, provided they turned off the avenue at the next opportunity.

This summer, following pressure from retailers, the city provided a new plan that allowed greater car access and truncated the busway by 11 blocks. Rather than require all personal vehicles to exit the busway onto the nearest side street, the proposal allowed cars to travel longer distances on Fifth Avenue before having to turn off.

Fifth Avenue currently has two bus lanes, no bike lane and three lanes for cars.

In Vornado’s slide show presentation, which was obtained by The New York Times, the company argues that the city should continue to allow continuous car traffic down Fifth Avenue, but reduce the number of car lanes from three to one.

It calls for rerouting some buses off Fifth Avenue. Buses, it says, have transformed the avenue “from a street for the people to an express highway.”

The presentation cites concerns that the city’s plan would imperil retail stores and hotels that have yet to recover from the pandemic.

“Leave the current busway as is — two dedicated bus lanes only,” the slide show says. “Do not implement proposed new turn restrictions that will confuse and congest.”

The presentation’s arguments echo those of the Fifth Avenue Association, a real estate-backed organization that has been campaigning against the original plan and whose chairman is a Vornado executive who oversees retail leasing for the company.

Mr. Gutman has said that expanding the city’s network of bus lanes was a priority, and the agency completed more than 16 miles of bus lanes in 2020, which city officials said was a record for a single year. This year, they had pledged to install or improve another 28 miles of bus lanes and busways.

Danny Pearlstein, a spokesman for Riders Alliance, an advocacy group for transit riders, said he was frustrated by the stalled Fifth Avenue busway and said that business leaders view the avenue primarily as a “retail playground” rather than a vital transportation corridor.

“For a mayor who prizes equity, saving bus riders time should be at the top of his agenda,’’ Mr. Pearlstein said.

Bus ridership has rebounded to between 1.4 million and 1.5 million daily riders, which is about 65 percent of prepandemic levels, according to the M.T.A.

“With gridlock gripping the city,” Mr. Pearlstein said, “there are few things more important to our recovery than fast, frequent and reliable bus service.”

By Anisa