A feud between New York City Transit and Vornado Realty Trust will keep an entrance to one of the city’s busiest subway stations – on the southeast corner of 59th Street and Lexington Avenue across from Bloomingdale’s – closed this holiday season and for the foreseeable future.

The lines of the battle have been drawn and detailed through correspondence, the most recent copies of which were made available to The New York Sun. The dispute remains at an impasse.

Meanwhile, the subway entrance is closed, though it is the only entrance to the southern end of a station that serves parts of the city’s busiest subway line: the uptown 4, 5, and 6, as well as the N, R, and W lines.

Vornado constructed the station entrance as part of its 54-story complex known as 731 Lexington Avenue, which was built on the site where the Alexander’s department store once stood. The sprawling, block-size building houses the headquarters for Mayor Bloomberg’s company, Bloomberg L.P., which completed the move into its new headquarters this summer. Other tenants include Citigroup, the clothing store H&M, and Home Depot.

But officials at New York City Transit have kept the roll gate the size of a garage door shuttered and locked since the station entrance was completed in February, forcing all of the riders who use the uptown station to exit and enter one block north on the corner of 60th Street and Lexington Avenue.

Transit official say snow and ice that sometimes blows off the 868-foot building make the entrance unsafe. The concern stems from two incidents this winter when an icicle fell from an upper story railing above the subway entrance and nearly hit a pedestrian.

In a letter to Vornado’s chairman Steven Roth dated September 21, the president of New York City Transit, Lawrence Reuter, wrote: “This entrance will remain closed until this issue is resolved so as to assure the safety of our customers.”

Mr. Reuter then added that transit officials would hold onto Vornado’s $1 million bond until “appropriate measures are taken.”

Vornado Realty, however, has refused to install a canopy over the entrance, arguing that it would do little to protect pedestrians and that the chances of snow and ice blowing off the building are rare. The company said it would defer on these matters to the police department, which is responsible for keeping the sidewalks safe. Vornado suggested temporarily closing off the sidewalk when necessary, an idea New York City Transit has rejected.

In his letter responding to Mr. Reuter and dated October 14, the president of Vornado’s New York City office, David Greenbaum, noted that transit officials had previously approved the entrance’s plans, which did not include a canopy. Then he went on to list a number of other changes New York Transit officials had requested of the company that were not included in the “MTA approved construction documents,” costing the company $114,000.

Mr. Greenbaum’s grievances also included a recent request made by the Metropolitan Transportation Authority’s to relocate a subway globe light because transit officials feared it would get hit by a truck.

Mr. Greenbaum concluded his letter, writing, “Your attention to these matters would be appreciated.”

The impasse in the heart of the city’s retail district comes as the holiday shopping season gets under way and transit officials offer discount fares be tween Thanksgiving and New Year’s, a giveback that will also serve to make the two staircases at the station’s 60th street entrance exceedingly crowded.

Elected leaders have been complaining about the closed station for months. The director of community affairs for city councilwoman Eva Moskowitz said the two parties should find a way to mitigate their concerns in order to open the entrance for the shopping season without compromising people’s safety.

“It’s commendable that the MTA doesn’t want to compromise on safety concerns but I think both sides need to work things out,” the Moskowitz aide, Jennifer Sedlis, said. Riders yesterday struggled to make sense of the locked gates and turnstiles that greeted them as they got off the uptown no. 6. Beyond the gates, the lights shined, the MetroCard vending machines were on and the wide stairs were spotless.

Diane Gonzalez, an attorney, was already late for a job interview on 57th Street. “You’d think 59th Street would be closer, but now I have to walk 3 blocks instead of two,” she said.